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How to care Large White Petunia

Large white petunia ( Petunia axillaris ) is a flowering herbaceous annual plant of the tobacco family (Solanaceae), native to South America. Because of its hardiness and elegant trumpet-shaped white flowers, it is a familiar garden plant, but still less common in gardens than its descendent - the garden petunia. Garden petunia is a hybrid of Petunia axillaris and Petunia integrifolia.

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Water

Twice per week

Sunlight

Full sun

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Basic Care Guide

Water

Watering of large white petunia once a week should be sufficient in most conditions but large white petunia plants in hanging baskets and other containers may require watering more frequently, especially in hot summer. A good watering medium is the use of a fine spray mist applied to soil and foliage to avoid water-logging of soils that can damage roots.

Ground Large white petunia

Large white petunia needs water regularly throughout the growing season.There are a few different ways you can go about determining how much water to give to your Large white petunia . Some gardeners choose to pick their water volume based on feeling the soil for moisture. That method suggests that you should water until you feel that the first six inches of soil have become moist. Beginning in spring, you should plan to water this plant about once per week.Typically, you should give a Large white petunia about two gallons of water per week, depending on how hot it is and how quickly the soil becomes dry. However, following strict guidelines like that can lead to overwatering if your plant requires less than two gallons per week for whatever reason. As the season presses on and grows warmer, you may need to increase your watering rate to about two to three times per week. Exceeding at this rate can be detrimental to your Large white petunia . With that said, you should also ensure that the soil in which your Large white petunia grows remains relatively moist but not wet, regardless of how often you must water to make that the case.

Potted Large white petunia

Watering a Large white petunia that lives in a pot is a bit different. Generally, you'll need to increase your watering frequency, as the soil in a pot can heat up and dry out a bit faster than ground soil. As such, you should plan to water a container-grown Large white petunia a few times per week in most cases, versus just once per week for an in-ground plant. You will need to use a different method to determine how much water to supply. Typically, you should give enough water to moisten all of the layers of soil that have become dry. To test if that is the case, you can simply stick your finger in the soil to feel for moisture. You can also water the soil until you notice a slight trickle of excess water exiting the drainage holes of your pot.

Large white petunia will move through several different growth stages throughout the year, some of which may require more water than others. For example, you will probably start your Large white petunia as a seed. While the seed germinates, you should plant to give more water than your Large white petunia will need later in life, watering often enough to maintain consistent soil moisture. After a few weeks, your Large white petunia will grow above the soil and may need slightly less water than at the seedling phase. Then, once this plant is mature, you can begin to use the regular watering frequency of about once per week. As flower development takes place, you may need to give slightly more water to aid the process.

Underwater and overwater

The remedy for underwatering a Large white petunia plant is somewhat obvious. When you notice that your plant lacks moisture, simply begin watering it on a more regular basis. The issue of overwatering can be a much more dire situation, especially if you fail to notice it early. When a Large white petunia is overwatered, it may contract diseases that lead to its decline and death. The best way to prevent this outcome is to choose a proper growing location, one that receives plenty of sunlight to help dry the soil and has good enough drainage to allow excess water to drain rather than pooling and causing waterlogged soils. If you overwater a Large white petunia that lives in a pot, you may need to consider changing it to a new pot. Your previous container may not have contained soil with good drainage or may not have had sufficient drainage holes. As you repot your overwatered Large white petunia , make sure to add loose soils and to use a pot that drains efficiently.

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What is the best way to water my Large white petunia?

To water Large white petunia, you can use a garden hose with a spray nozzle, a watering can, or just about any other common watering tool. Generally, Large white petunia is not too picky about how they receive their water, as they can live off of rainwater, tap water, or filtered water. Often, you should try not to water this plant from overhead, as doing so can damage the leaves and flowers and may lead to disease as well. At times, the best method for watering this plant is to set up a drip irrigation system. These systems work well for Large white petunia as they apply water evenly and directly to the soil. For one Large white petunia that grows in a container, you can use a similar watering approach while changing the tools you use. To water a container-grown Large white petunia, use a cup, watering can, or your tap to apply water directly to the soil.

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What should I do if I water my Large white petunia too much or too little?

The remedy for underwatering Large white petunia is somewhat obvious. When you notice that your plant lacks moisture, simply begin watering it on a more regular basis. The issue of overwatering can be a much more dire situation, especially if you fail to notice it early. When your Large white petunia is overwatered, it may contract diseases that lead to its decline and death. The best way to prevent this outcome is to choose a proper growing location, one that receives plenty of sunlight to help dry the soil and has good enough drainage to allow excess water to drain rather than pooling and causing waterlogged soils. If you overwater your Large white petunia that lives in a pot, you may need to consider changing it to a new pot. Your previous container may not have contained soil with good drainage or may not have had sufficient drainage holes. As you repot your overwatered Large white petunia, make sure to add loose soils and to use a pot that drains efficiently.

How often should I water my Large white petunia?

Large white petunia needs water regularly throughout the growing season. Beginning in spring, you should plan to water this plant about once per week. As the season presses on and grows warmer, you may need to increase your watering rate to about two to three times per week. Exceeding at this rate can be detrimental to your Large white petunia. With that said, you should also ensure that the soil in which your Large white petunia grows remains relatively moist but not wet, regardless of how often you must water to make that the case. Watering Large white petunia that lives in a pot is a bit different. Generally, you'll need to increase your watering frequency, as the soil in a pot can heat up and dry out a bit faster than ground soil. As such, you should plan to water a container-grown Large white petunia a few times per week in most cases, versus just once per week for an in-ground plant.

How much water does my Large white petunia need?

There are a few different ways you can go about determining how much water to give to your Large white petunia. Some gardeners choose to pick their water volume based on feeling the soil for moisture. That method suggests that you should water until you feel that the first six inches of soil have become moist. Alternatively, you can use a set measurement to determine how much to water your Large white petunia. Typically, you should give your Large white petunia about two gallons of water per week, depending on how hot it is and how quickly the soil becomes dry. However, following strict guidelines like that can lead to overwatering if your plant requires less than two gallons per week for whatever reason. When growing Large white petunia in a container, you will need to use a different method to determine how much water to supply. Typically, you should give enough water to moisten all of the layers of soil that have become dry. To test if that is the case, you can simply stick your finger in the soil to feel for moisture. You can also water the soil until you notice a slight trickle of excess water exiting the drainage holes of your pot.

How can I tell if i'm watering my Large white petunia enough?

It can be somewhat difficult to avoid overwatering your Large white petunia. On the one hand, these plants have relatively deep roots that require you to moisten the soil weekly. On the other hand, Large white petunia are plants that are incredibly susceptible to root rot. Along with root rot, your Large white petunia may also experience browning as a result of overwatering. Underwatering is far less likely for your Large white petunia as these plants can survive for a while in the absence of supplemental watering. However, if you go too long without giving this plant water, it will likely begin to wilt. You may also notice dry leaves.

How should I water my Large white petunia through the seasons?

You can expect your Large white petunia’s water needs to increase as the season moves on. During spring, you should water about once per week. Then, as the summer heat arrives, you will likely need to give a bit more water to your Large white petunia, at times increasing to about three times per week. This is especially true of Large white petunia that grow in containers, as the soil in a container is far more likely to dry out faster than ground soil when the weather is warm. In autumn, while your Large white petunia is still in bloom, it may need a bit less water as the temperature has likely declined, and the sun is no longer as strong as it was in summer.

How should I water my Large white petunia at different growth stages?

Large white petunia will move through several different growth stages throughout the year, some of which may require more water than others. For example, you will probably start your Large white petunia as a seed. While the seed germinates, you should plant to give more water than your Large white petunia will need later in life, watering often enough to maintain consistent soil moisture. After a few weeks, your Large white petunia will grow above the soil and may need slightly less water than at the seedling phase. Then, once this plant is mature, you can begin to use the regular watering frequency of about once per week. As flower development takes place, you may need to give slightly more water to aid the process.

What's the difference between watering Large white petunia indoors and outdoors?

There are several reasons why most Large white petunia grow outdoors rather than indoors. The first is that these plants typically grow to tall. The second reason is that Large white petunia needs more daily sunlight than most indoor growing locations can provide. If you are able to provide a suitable indoor growing location, you may find that you need to give your Large white petunia water a bit more often than you would in an outdoor growing location. Part of the reason for this is that indoor growing locations tend to be a lot drier than outdoor ones due to HVAC units. The other reason for this is that soil in containers can dry out relatively quickly as well compared to soil in the ground.

Fertilizer

In summer, a balanced liquid fertilizer contains roughly equal proportions of the three main elements (N％-P2O5％-K2O％) with 8-8-8 or 12-12-12 can be used every two to three weeks. Spreading varieties will respond well to weekly fertilization. Some varieties such as those with double flowers will enjoy twice-weekly doses of fertilizer. If growing large white petunia in containers or baskets, opt for a time-release fertilizer.

However, care should be taken not to over-fertilize large white petunia, particularly with nitrogen. this can lead to pest and disease issues. Over-fertilization can be identified by large white petunia leaves turning yellow or brown.

Large white petunia, a bright and cheerful annual or perennial as cool-weather annuals（tender perennial but is most often grown as an annual）, is a welcome sign of gardening season to most. When it makes its first appearance in the stores and nurseries for the year, folks get right to work planning out their gardens to include Large white petunia amongst their favorites.

Plants need nutrients to survive; most gardeners, regardless of experience, are well aware of this factor. However, without food, Large white petunia will die out soon after the first pollination. Therefore, providing the right type of nutrients in the right amounts is the best way to keep Large white petunia going throughout the blooming season and producing large, beautiful flowers. Fertilizer also helps Large white petunia build a large, healthy root system. This plant needs all the help it can get since its root system is very thin and easily damaged. Fertilizing at planting helps Large white petunia build a solid root structure that not only provides stability to the plant, but also sets the stage for a sensational flowering performance. When timed correctly, fertilization can greatly extend Large white petunia's flowering period.

Large white petunia puts on tremendous growth early in the growing season, once the danger of the last frost has passed. It’s during this time that Large white petunia should be fertilized; more specifically, during planting. The idea is to apply when the plant is first planted in the ground or in planters; however you choose to plant it. This will be the only dose of fertilizer until later in the year, when blooms are in full force.Once the season is in full swing and Large white petunia has opened most of its blooms at full size, it’s time to start fertilizing again. Around the time when blooms are at peak output, begin fertilizing again once every three to four weeks, as weather permits. Then, after Large white petunia starts to put out fewer new blooms, stop fertilizing; there’s no need to fertilize when the plant can’t produce any more blooms.

Most types of Large white petunia need the same general balance of nutrients from fertilizer. These should come in the form of a fertilizer that’s formulated specifically for high-yield blooming plants. A fertilizer with a higher level of phosphorus is the best option. This type of fertilizer has a higher P number in its NPK number, for example 10-30-10.Several fertilizer brands sell a fertilizer that’s perfect for blooming plants like Large white petunia, which are an easy and fuss-free way to provide the right nutrients. If you do choose to use a pre-mixed fertilizer, follow the directions on the package to prevent Large white petunia from getting too much or too little fertilizer, both of which can cause the plant to grow poorly or even wilt entirely.Depending on the type of fertilizer you have, specific fertilizing instructions may vary. However, there are a few general tips for applying most types of fertilizer to Large white petunia. The first fertilizer application, which should be when you first plant Large white petunia, will likely consist of mixing the recommended amount of fertilizer into the soil before planting and watering in the Large white petunia. Subsequent fertilizing may look a little different. For pellet fertilizers, simply mix the pellets into the top inch of soil around the outer edge of the plant, where the roots are. Water them in very well at first, then water regularly after that. Other fertilizers may be mixed into a watering can and applied just like a regular watering. Follow any instructions on fertilizer packaging for consistency, but if you’d rather keep things on a regular schedule, shoot for every three to four weeks.

Over-fertilizing is a very easy mistake to make for first-time gardeners, or even for experienced gardeners trying out a new product. Fortunately, Large white petunia makes this issue known very well by displaying several signs of distress. You may notice that its leaves are yellowing quickly, the foliage may wilt, or new blooms may be under-developed. These are all clear signs of too much food.When you fertilize Large white petunia too frequently, you create uninhabitable soil conditions. Soil may become too hot, which is a term used to describe when soil is too saturated with minerals, nutrients, or compost, and ends up burning the roots of anything planted in it. It’s a good idea to flush out the soil well once a month or so, just by watering twice as much as normal with good drainage.

While regular fertilizing is important for Large white petunia, it absolutely can be applied at the wrong time. Some situations call for holding back the fertilizer once in a while. These are usually climate related, but they also include a variety of controllable factors. Essentially, when something is wrong with the plant, the soil, or the climate, wait it out until things have been smoothed over and the plant has recovered.An example of when not to fertilize is if there are severe or unexpected changes in the weather. If a cold nap suddenly comes in the middle of summer, wait until it’s warm again to start fertilizing. The same stands for if the soil becomes too dry or too packed to absorb anything. At this point, fertilizer will be going straight to the roots, rather than being diffused by soil before it reaches them. As you can imagine, the roots of Large white petunia aren’t very fond of that.When temperatures soar during the hottest parts of the day into the 90-degree fahrenheit range, don’t apply fertilizer. Since fertilizer can be broken down at various speeds depending on temperature, it’s especially important not to allow hot temperatures to break it down too quickly. Pests or diseases should also be treated and cleared up before re-fertilizing.

Why do I need to fertilize my Large white petunia?

Plants need nutrients to survive; most gardeners, regardless of experience, are well aware of this factor. However, without food, Large white petunia will die out soon after the first pollination. Therefore, providing the right type of nutrients in the right amounts is the best way to keep Large white petunia going throughout the blooming season and producing large, beautiful flowers.

Fertilizer also helps Large white petunia build a large, healthy root system. This plant needs all the help it can get since its root system is very thin and easily damaged. Fertilizing at planting helps Large white petunia build a solid root structure that not only provides stability to the plant, but also sets the stage for a sensational flowering performance. When timed correctly, fertilization can greatly extend Large white petunia's flowering period.

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When is the best time to fertilize my Large white petunia?

Large white petunia puts on tremendous growth early in the growing season, once the danger of the last frost has passed. It’s during this time that Large white petunia should be fertilized; more specifically, during planting. The idea is to apply when the plant is first planted in the ground or in planters; however you choose to plant it. This will be the only dose of fertilizer until later in the year, when blooms are in full force.

Once the season is in full swing and Large white petunia has opened most of its blooms at full size, it’s time to start fertilizing again. Around the time when blooms are at peak output, begin fertilizing again once every three to four weeks, as weather permits. Then, after Large white petunia starts to put out fewer new blooms, stop fertilizing; there’s no need to fertilize when the plant can’t produce any more blooms.

When should I avoid fertilizing my Large white petunia?

While regular fertilizing is important for Large white petunia, it absolutely can be applied at the wrong time. Some situations call for holding back the fertilizer once in a while. These are usually climate related, but they also include a variety of controllable factors. Essentially, when something is wrong with the plant, the soil, or the climate, wait it out until things have been smoothed over and the plant has recovered.

An example of when not to fertilize is if there are severe or unexpected changes in the weather. If a cold nap suddenly comes in the middle of summer, wait until it’s warm again to start fertilizing. The same stands for if the soil becomes too dry or too packed to absorb anything. At this point, fertilizer will be going straight to the roots, rather than being diffused by soil before it reaches them. As you can imagine, the roots of Large white petunia aren’t very fond of that.

When temperatures soar during the hottest parts of the day into the 90-degree fahrenheit range, don’t apply fertilizer. Since fertilizer can be broken down at various speeds depending on temperature, it’s especially important not to allow hot temperatures to break it down too quickly. Pests or diseases should also be treated and cleared up before re-fertilizing.

What type of fertilizer does my Large white petunia need?

Most types of Large white petunia need the same general balance of nutrients from fertilizer. These should come in the form of a fertilizer that’s formulated specifically for high-yield blooming plants. A fertilizer with a higher level of phosphorus is the best option. This type of fertilizer has a higher P number in its NPK number, for example 10-30-10.

Several fertilizer brands sell a fertilizer that’s perfect for blooming plants like Large white petunia, which are an easy and fuss-free way to provide the right nutrients. If you do choose to use a pre-mixed fertilizer, follow the directions on the package to prevent Large white petunia from getting too much or too little fertilizer, both of which can cause the plant to grow poorly or even wilt entirely.

How do I fertilize my Large white petunia?

Depending on the type of fertilizer you have, specific fertilizing instructions may vary. However, there are a few general tips for applying most types of fertilizer to Large white petunia. The first fertilizer application, which should be when you first plant Large white petunia, will likely consist of mixing the recommended amount of fertilizer into the soil before planting and watering in the Large white petunia.

Subsequent fertilizing may look a little different. For pellet fertilizers, simply mix the pellets into the top inch of soil around the outer edge of the plant, where the roots are. Water them in very well at first, then water regularly after that. Other fertilizers may be mixed into a watering can and applied just like a regular watering. Follow any instructions on fertilizer packaging for consistency, but if you’d rather keep things on a regular schedule, shoot for every three to four weeks.

What happens if I fertilize my Large white petunia too much?

Over-fertilizing is a very easy mistake to make for first-time gardeners, or even for experienced gardeners trying out a new product. Fortunately, Large white petunia makes this issue known very well by displaying several signs of distress. You may notice that its leaves are yellowing quickly, the foliage may wilt, or new blooms may be under-developed. These are all clear signs of too much food.

When you fertilize Large white petunia too frequently, you create uninhabitable soil conditions. Soil may become too hot, which is a term used to describe when soil is too saturated with minerals, nutrients, or compost, and ends up burning the roots of anything planted in it. It’s a good idea to flush out the soil well once a month or so, just by watering twice as much as normal with good drainage.

Sunlight

The most important factor in growing of large white petunia is sunlight. Large white petunia needs at least five hours of sunlight per day. They will thrive best and grow the most flowers with exposure to full, all-day sunlight. The plants will grow in partial shade but will have fewer flowers. Lack of sunlight may also lead to leggy plants and a lack of healthy flowering.

Large white petunia seeds require plenty of sunlight for germination. Be sure to plant or prepare seed trays somewhere with plenty of exposure to sunlight.

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How much sunlight should Large white petunia get per day to grow healthily?

You must expose the plants to at least 6 to 8 hours of sunlight daily. They prefer more exposure to the morning light, especially in the summer. The Large white petunia needs full sun and more sunlight that it can get. The more light these species get, the more they can manufacture food, produce beautiful blooms, and survive.

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What type of sunlight does Large white petunia need?

The Large white petunia grows best under full sunlight. It's best not to crowd them together so they can get exposure to the sun evenly. The leaves shouldn't be starved with sunlight. If planted in pots, try to expose the herbaceous flowers in windows with direct sun and ensure they receive full sunlight regardless of the months.

They don't tend to do well in partial or filtered light as this will not produce strong stems and healthy flowers. It's best if the Large white petunia is always exposed to the sun.

Can sunlight hurt plants? How to protect Large white petunia from sun and heat damage?

When the temperature rises above 90℉(32℃), the Large white petunia can get damaged by extreme temperatures, especially if they are exposed to many hours of sun. It's always ideal for providing some shade from the light in the afternoon in the summer. It's always important to keep in mind that the sunlight in the summer is stronger than the one in the winter. Sunlight exposure is also 50% longer in the summer than in the winter.

If the Large white petunia is too stressed with sunlight, you might want to keep them fully hydrated. Water them when the top of the soil is about 2 inches dry, and move the plants indoors if it's too hot outside. This is the case if they are planted in containers.

It can be normal for the plant leaves to wilt during the day. Generally, they can recover at night. However, when you notice that the Large white petunia is still drooping, this means that the plant is losing water fast, and you need to water them.

Should I protect Large white petunia from sun exposure?

The Large white petunia does not need any protection from the sun. In fact, they love the sun, and some species are heliotropic. Plant them in south-facing gardens whenever possible so they can be exposed from morning to afternoon. While the sun can benefit them, some may experience a sunburn. You might offer protection from the afternoon and midday sun through a shade of a tree or a wall.

Growing the Large white petunia in shady areas is impossible because the larger flowers would require a lot of energy to grow and produce. Always provide the lighting conditions and set them in an area with full sun for best results.

What will happen if Large white petunia gets inadequate sunlight?

When the Large white petunia does not get adequate sunlight, or they are not placed in full sun locations, it's worth noting that the photosynthetic process will slow down. A lack of sunlight will cause the stems to become more leggy since they become thin and long since they tend to seek too much sunlight. They will not bloom and produce seeds in the shade.

Inadequate sunlight will also mean that the older leaves can die, the color of the new ones is lighter than the old foliage, and the new growth is smaller than the last ones.

The Large white petunia indeed loves the sun so much. However, they can wilt when exposed to excessive heat and ultraviolet light during the extreme summer months, so be careful. You might want to cover them with a net that has a green shade, especially in the summer, to prevent the leaves and the flowers from scorching. When they are indoors, reduce the heat with the help of a fan.

Does Large white petunia need special care about sunlight during its different growth stages?

When the Large white petunia is growing, they need more light than their mature counterparts. The younger ones should receive adequate light, but they might not be prepared for sudden full sunlight, especially if they are grown in a nursery. They can be more sensitive to the summer sun, so the lighting should be gradual and slow.

How much light does Large white petunia need for photosynthesis?

During summer or late spring, the Large white petunia needs 6 to 8 hours of direct light every single day. This is whether they are planted outdoors. If the Large white petunia is planted in pots or you're growing them in the winter, they need direct fluorescent lights that help them grow better. Make sure to place them in an indoor area where they are facing south or east so they can have enough sunlight for photosynthesis.

Are there any cautions or tips for sunlight and Large white petunia?

When transplanting the plants, they should not be exposed to sudden sunlight. Give the Large white petunia to grow and mature before transplanting outside. Some species of herbaceous plants can grow taller and might cast a shade on other young plants. Allow between 80 to 100 days of growing season before planting another batch to ensure that every plant receives more than enough sunlight for at least 6 hours a day.

Make sure that the Large white petunia receives the best light possible, especially if it's planted in a nursery. These are sun-loving plants, but too much sunlight with a very hot temperature is also detrimental to their growth. Indoor lights should be replaced with natural sunlight as much as possible since these species crave this every day.

Pruning

During the season, deadhead any flowers which have died to keep the area free of sites which may harbor pests and disease. Large white petunia flowers die fairly quickly so deadheading should be performed regularly. Doing so will help the growth of new flowers and prolong blooming.

Is pruning necessary for my Large white petunia?

Large white petunia is a kind of annual plant so it doesn't need much pruning. You only need to cut off and clean the diseased, yellow or dropped leaves and stems during its growing period. This will help your Large white petunia to stay away from pathogens infection.

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How do I prune my Large white petunia?

During the growth of the plant, yellowing, drying and spotted leaves are produced, and these spotted and discolored leaves need to be trimmed off. If the whole piece of leave is discolored or infected, you will need to cut it off completely. In other situations, you will only need to cut off the discolored or infected part on certain leaves. Large white petunia above the ground will die and dry up in the winter, and the dead plants need to be cleaned up.

Are there any cautions I should be careful with when pruning my Large white petunia?

Large white petunia leaves are delicate, so take care not to score or bruise them. Unless the leaves are withered or heavily discolored, do not prune the leaves from the lowermost branches unless they’re damaged. They typically grow the largest, so they supply the plant with critical energy to keep it growing right. Please prevent the wounds from water after pruning until they are fully recovered. Remember always sterilize the tools before pruning. When the pruning is finished, please throw all the waste leaves and stems into the trashbins to avoid diseases and bugs.

Are there any tips for pruning my Large white petunia?

Sterilize all the tools before pruning; unclean tools will pass pathogens to the plant through wounds;
Prune on sunny days because the new cuts will be infected by pathogens if they're distained by rain or water.
Throw all the waste leaves and stems into trashbins, they will easily rot and attract diseases and bugs

When should/shouldn't I prune my Large white petunia?

Expect to prune your Large white petunia every week if it’s growing well or every two weeks if it grows slowly. It is always good to prune it on sunny days because if you prune it on rainy days, the rainwater will distain the cuts and cause the whole plant to be infected.

What should I look for when pruning my Large white petunia in different seasons?

Because Large white petunia is an annual plant, the pruning should take place basically during the seasons that the plant grows rapidly. During the growth of the plant, yellowing, drying and spotted leaves are produced, and these spotted and discolored leaves need to be trimmed off.

Advanced Care Guide

Temperature

On account of its South American origins, large white petunia can tolerate high temperatures but will not tolerate frost. Though classed as tender perennials, most large white petunia will not survive winter conditions and live as annuals. They are not a hardy genus and will only survive in a warm area. Night-time temperatures should stay above 14 ℃ and daytime temperatures above 16 ℃.

Large white petunia likes moist substrate but does not tolerate waterlogging, because soggy soil will cause root rot.

What is the optimal temperature for Large white petunia?

For this tropical plant to thrive, you’ll want to keep them between 75℉ and 90℉ (25-32℃). Each species can handle temperatures outside of this range, but keeping it within several degrees of these limits will ensure they grow to their maximum potential.

As for its extreme temperature limits, any environment below 50℉ (10℃) or above 95℉ (35℃) will begin to hinder its growth and cause various aberrations to its leaves and stems. This is especially true with low temperatures; even a light frost can cause your tropical plants to perish. Cellular death can begin to happen at a rapid pace, with some species dying in as little as 12 to 24 hours.

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Does Large white petunia require different temperatures for different growing phases?

While Large white petunia doesn’t require any changes in temperature to enter different growing phases, it is important to stay consistent. Wild temperature fluctuations can slow down its growth regardless of its current phase, so it's always better to keep them in a controlled environment. That optimal temperature range of 75℉ and 90℉ (25-32℃) is vital to maintain, especially staying above the lower limit. Going above 90℉(32℃) isn’t ideal, but as tropical plant it won’t suffer too much. On the other hand, going below 50℉ (10℃) (and especially 40℉/5℃) will begin to directly damage this heat-loving plant species.

Does Large white petunia need different temperatures for different seasons?

Large white petunia does not need different temperatures for different growing seasons. The most important step in seasonal care is to keep the environment within the optimal temperature range. That's why it's always best to keep this plant indoors. That way, you can control the temperature no matter what the climate is like outside.

Light is also important for tropical species, with all of these plants preferring a partial side level of sun exposure. This means any light they receive needs to be dappled or filtered, with bright but indirect light being the best option when growing your plants indoors. Too much direct sunlight can negatively affect your plant’s leaves, reducing its growth potential.

What are the temperature guidelines to keep your Large white petunia healthy?

Tip #1: Don’t Leave Your Plant Near Windows in Colder Months

If you want to make sure your plant isn’t exposed to colder temperatures, you may want to keep them away from windows. In colder months like late fall and winter, even the smallest draft can leak cold air into your home through cracks in your windows. While this air usually dissipates and warms up as it travels throughout your home, any plants placed in close proximity to the window will be affected. Move your tropical plants into an area where they will still get bright but indirect light, while making sure they won’t be affected by potential drafts.

Tip #2: If You Find Dry Patches, Your Plant May Be Getting Too Much Sunlight or Heat

You may notice the leaves become white or even scorched on a sunny day. These discolorations and unusual markings usually indicate that a plant is getting too much heat or sunlight, and it may be dehydrated. Excess light and heat will dry out the soil, stopping plants from getting the moisture they need to support their cellular structure. It also slows down or stops the process of photosynthesis, further hindering growth. If ignored for too long, these dry spots can spread and eventually result in the death of your plants.

Tip #3: Avoid Frost at All Costs

Colder temperatures and frost can damage your plants by causing ice crystals or disrupt normal physiological activity. This makes it nearly impossible for water to move freely throughout plant tissue, creating a deficit of moisture in their stems and leaves. You can tell a plant has been damaged by frost if it begins to suffer from hydrosis (it will appear as though it's soaked with water.) If the problem persists, your plants may begin shriveling and turning a dark brown or black hue. After that, the plant will almost certainly die.

What is the best way to maintain the right temperature for my Large white petunia?

The best way to maintain the right temperature range for Large white petunia is by keeping an eye on both the climate and humidity. You’ll want to try to keep each species in a room where you have access to climate control, keeping the heat in the temperature range best mimics its natural habitat. The humidity levels will also have a direct effect on temperature, so it's important to monitor these as well. You can artificially raise the humidity of your growing space by using a humidifier or lightly misting the leaves with water.

If you intend to grow this species outside, you may find it difficult to maintain the right balance of temperature and humidity. If temperatures begin to drop or the air becomes too dry, your best option is to find room within your home and move your plant inside. An indoor growing space will allow you to control the climate more closely, helping your plant reach its full potential.

Soil

Large white petunia will thrive best in fertile soil with high organic matter content such as peat moss, well-decomposed compost or manure. If potting, soil needs to be lightweight to allow water to drain away. Dense soil with poor drainage is easy to accumulate water, making large white petunia roots wet and causing them to rot away. As with many ornamental plants, petunias prefer slightly acidic soil (pH 6.0–7.0).

Planting

Large white petunia can be grown from seed though growing from transplants is easier. Transplants should be positioned in light, well-drained soil with exposure to full sun shortly after the last frost in spring.

If growing from seed, start the seeds indoors 10-12 weeks before taking them outside. The seedlings can be taken outside once they have three leaves, and the placing of plastic wrap over the seedlings outdoors will help keep temperature and humidity constant to help in their development.

Whether growing from seed or transplanting large white petunia, a location should be chosen with minimal exposure to wind and each plant given a space of 30 cm. Large white petunia should not be planted in the area where diseases have once occurred, since they are susceptible to diseases. If planting in pots use a soil-less mix to keep cultivation substrate light large white petunia free of disease.

Seasonal Care Tips

Summer

Fall

Winter

This plant and other annuals benefit from some care in the summer.

1

Keep the soil consistently moist, especially when rainfall is scarce. When the plant’s leaves begin losing some of the glossy shine, it’s time to water.

2

Continue to apply monthly applications of an all-purpose fertilizer.

3

Remove any spent blooms to encourage reflowering.

4

Ensure the plant is still receiving several hours of sunlight. Container plants may require relocating to another area.

5

Keep an eye out for any pests and diseases and remove debris from around the plant’s base.

As long as the plant is growing in the fall:

1

continue to care for your plant by watering and fertilizing with the all-purpose mixture. These steps will keep your annuals to keep them moist, shiny, and well-fed. If you'd rather not have your plant spread via seeds, deadhead spent blooms.

2

Some annuals may benefit from being cut back by 1/4 during the autumn.

3

To attempt to propagate more plants during the fall, you can either let your plant go to seed or sow the seeds yourself.

4

Depending on the variety, some plants do best in full sun while others need partial shade.

Your plant will only require minimal care during the colder winter months.

1

To overwinter your plant best, move it to a pot and bring it indoors, or take a cutting and propagate a new plant. As long as it isn't exposed to colder temperatures, there's a chance that your annual plant can thrive and last until spring, depending on the variety of your plant.

2

Make sure you continue providing enough light and occasional water for your overwintering annual to give it the best chance.

Common Pests & Diseases

Common issues for Large white petunia based on 10 million real cases

Wilting after blooming

Flowers may wither for a variety of reasons.

Solutions: Check the soil or potting medium. Coarse textures can allow water to drain too rapidly, preventing the plant from taking up enough. If the soil and roots seem very dry, add sphagnum moss or other mediums that hold water. Water according to recommendations for each plant's species. Low humidity can be corrected by misting the plant regularly or placing it near a humidifier. Keeping it near other plants helps, too. Keep the environment consistent in terms of temperature, humidity, and lighting. Keep it away from vents, heaters, and air conditioners, and avoid moving it to locations where it will experience a temperature shock. Hot, dry heat, and cold drafts are problematic for many plants. Especially if the plant is outside, it could be experiencing heat or light stress. Try moving it to a shadier location.

Leaf beetles

Leaf beetles are a class of colored insects 1 to 2 cm in size. They gnaw on leaves and petals resulting in small, round holes scattered over the surface.

Solutions: For less serious cases: Remove beetles, nymphs, and eggs. Remove all life stages of the beetles and kill them by placing them in a bucket of warm, soapy water. This can be done more easily by placing the bucket under affected leaves and shaking the plant. This method is most effective in the afternoon when leaf beetles are more active. Always dispose of insects in a sealed bag or container to avoid escape and spread. To treat more serious infestations: Apply organic insecticides. Use naturally-derived insecticides before moving on to synthetic insecticides. Neem oil and pyrethrum are naturally-derived insecticides that should be applied following label instructions. Apply synthetic insecticides. Examples of insecticides effective for leaf beetles include carbaryl, permethrin, and bifenthrin. Apply insecticides according to label instructions.

Flower withering

Flowers may dry out due to a sudden change in environment or because the plant has completed its normal flowering period.

Solutions: If flower withering is a natural progression due to age, there is nothing that can be done to slow or stop the process. Once hormones within the plant begin the process of senescence, it’s irreversible. For lack of water, immediately water the plant using room temperature rainwater, bottled spring water, or filtered tap water. Water container plants until excess water drains out the bottom; water in-ground plants until the soil is soaked but there isn’t standing water on the surface. In the event of nutritional deficiencies, the best solution is to use a granular or water-soluble liquid fertilizer, and apply it to the soil at about half the recommended dosage. Keep it off the leaves and make sure granular products are watered into the soil well. If the plant is infected with a bacterial or fungal pathogen, there is no course of treatment that cures the diseased plants. The best solution is to remove the infected plants and dispose of the plant material off-site. Do not put in a compost pile.

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More About Large White Petunia

Plant Type

Herb

Lifespan

Annual, Perennial, Biennial

Spread

25 cm

Leaf Color

Green

Flower Size

4 to 6 cm

Plant Height

25 to 60 cm

Name story

Large white petunia

Petunia axillaris can be regarded as the earliest ancestor of the petunia genus while the current hybrids basically developed from this particular species. The most amazing thing about this plant is that it has huge white flowers which is also why it is called the large white petunia.

White moon petunia

Many people choose to plant it along a courtyard wall. When the evening approaches, the moonlight shines on the white flowers highlighting its elegance and grace. What's magical about it is that its flowers emanate a sweet vanilla scent at night, adding a delicate atmosphere to the surroundings. Therefore, people decided to give it a tender name, the white moon petunia.

Usages

Garden Use

The large white petunia is one of the most common flowers grown in pots and other containers. It loves to be crowded, so planting in bunches or mixed together with other annuals will help them grow splendidly. The large white petunia is prized for its waterfall of large, fast-growing flowers and ease of care, which is what makes it so great in containers, courtyard gardens and cottage gardens. Calibrachoa, sweet potato vine, and lobelia make great companions.

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Common Problems

My large white petunia is wilting. What is the problem?

Large white petunia may wilt if soils become too water-logged or if they are dry. Too little or too much water will reduce root growth and cause the plants to wilt. If this is noticed, first check to see if the soil is very dry. If so, water the plant. If it is too moist, waterlogging may be the problem. Waterlogging is the most common problem to large white petunia and will manifest as wilting plants. Soil should be dried out at least once before watering the plants.

My large white petunia is growing very few or small flowers. What is the problem?

Sometimes, large white petunia may not flower or grow small, undeveloped flowers. Poor flowering of large white petunia is most likely to be a lack of sunlight. Consider moving other plants to ensure that the large white petunia is receiving adequate sunlight.

My petunias have grown leggy with droopy flowers. What should I do?

Large white petunia stems may sometimes grow long and flowers droop. If this has happened, petunias should be trimmed back in midsummer by removing half of the plant stem’s length using garden shears. this will force the flowers to grow new, more compact stems and full flowers. Remember to put your large white petunia in a place with plenty of sunlight.

Plants with Same Care Needs

Poison ivy

In pop culture, poison ivy is a symbol of an obnoxious weed because, despite its unthreatening looks, it gives a highly unpleasant contact rash to the unfortunate person who touches it. Still, it is commonly eaten by many animals, and the seeds are a favorite with birds. The leaves turn bright red in fall. Its sister species, Western poison ivy (Toxicodendron rydbergii), is not considered to be invasive in the United States, but is noxious in Australia and New Zealand.

Bloom Time

Mid spring

Garden phlox

The garden phlox is a flowering plant that is native to the United States. The name, phlox, comes from the Latin for "flame," reflecting its bright colors. Garden phlox flowers can become important food sources for insects and hummingbirds.

Bloom Time

Mid spring

Ground ivy

Ground ivy (Glechoma hederacea) is a perennial evergreen trailing plant, often found in grasslands and woodlands. Saxon peoples once spread the plant, but it has become invasive in some parts of the world now. The fast-growing ground ivy can be toxic to horses but generally cannot harm other animals or humans.

Bloom Time

Mid spring

Persian silk tree

Albizia julibrissin, colloquially known as persian silk tree, is a deciduous plant with characteristic pink, fuzzy inflorescences. Persian silk tree is mainly cultivated for decorative purposes. Its flowers have a mild, sweet smell and are often visited by butterflies, bees and hummingbirds.

Bloom Time

Mid spring

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How to care Large White Petunia

Symbolism

Basic Care Guide

Water

Water

Never miss a care task again!

Fertilizer

Fertilizer

Sunlight

Know the light your plants really get.

Pruning

Advanced Care Guide

Temperature

Soil

Planting

Seasonal Care Tips

Summer

Fall

Winter

This plant and other annuals benefit from some care in the summer.

As long as the plant is growing in the fall:

Your plant will only require minimal care during the colder winter months.

Common Pests & Diseases

Treat and prevent plant diseases.

More About Large White Petunia

Name story

Usages

Find your perfect green friends.

Common Problems

My large white petunia is wilting. What is the problem?

My large white petunia is growing very few or small flowers. What is the problem?

My petunias have grown leggy with droopy flowers. What should I do?

Plants with Same Care Needs

Botanist in your pocket

App

How to care Large White Petunia

Symbolism

Basic Care Guide

Water

Water

Never miss a care task again!

Fertilizer

Fertilizer

Sunlight

Know the light your plants really get.

Pruning

Advanced Care Guide

Temperature

Soil

Planting

Seasonal Care Tips

Summer

Fall

Winter

This plant and other annuals benefit from some care in the summer.

As long as the plant is growing in the fall:

Your plant will only require minimal care during the colder winter months.

Common Pests & Diseases

Treat and prevent plant diseases.

More About Large White Petunia

Name story

Usages

Find your perfect green friends.

Common Problems

My large white petunia is wilting. What is the problem?

My large white petunia is growing very few or small flowers. What is the problem?

My petunias have grown leggy with droopy flowers. What should I do?

Plants with Same Care Needs