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Matted St. John's-wort
Matted St. John's-wort
Matted St. John's-wort
Matted St. John's-wort
Matted St. John's-wort
Matted St. John's-wort
Add to My Garden
Matted St. John's-wort
Hypericum japonicum
Also known as: Japanese St. John's wort
Matted St. John's-wort (Hypericum japonicum) is a widespread wildflower that occurs in a large variety of mainly damp tropical habitats from rice fields to grasslands. While it isn't a common ornamental species, its dense and compact growth forms make it a good candidate for ground cover. Its small yellow flowers offer up to six months of garden interest.
Planting Time
Planting Time
Spring
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Habitat

Wet places in lowland, rice fields, ditches, marshes, grasslands, waste places, bog garden
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Questions About Matted St. John's-wort

Watering Watering Watering
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What is the best way to water my Matted St. John's-wort?
To water Matted St. John's-wort, you can use a garden hose with a spray nozzle, a watering can, or just about any other common watering tool. Generally, Matted St. John's-wort 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 Matted St. John's-wort as they apply water evenly and directly to the soil. For one Matted St. John's-wort that grows in a container, you can use a similar watering approach while changing the tools you use. To water a container-grown Matted St. John's-wort, 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 Matted St. John's-wort too much or too little?
The remedy for underwatering Matted St. John's-wort 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 Matted St. John's-wort 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 Matted St. John's-wort 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 Matted St. John's-wort, make sure to add loose soils and to use a pot that drains efficiently.
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How often should I water my Matted St. John's-wort?
Matted St. John's-wort 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 Matted St. John's-wort. With that said, you should also ensure that the soil in which your Matted St. John's-wort grows remains relatively moist but not wet, regardless of how often you must water to make that the case. Watering Matted St. John's-wort 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 Matted St. John's-wort a few times per week in most cases, versus just once per week for an in-ground plant.
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How much water does my Matted St. John's-wort need?
There are a few different ways you can go about determining how much water to give to your Matted St. John's-wort. 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 Matted St. John's-wort. Typically, you should give your Matted St. John's-wort 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 Matted St. John's-wort 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.
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How can I tell if i'm watering my Matted St. John's-wort enough?
It can be somewhat difficult to avoid overwatering your Matted St. John's-wort. On the one hand, these plants have relatively deep roots that require you to moisten the soil weekly. On the other hand, Matted St. John's-wort are plants that are incredibly susceptible to root rot. Along with root rot, your Matted St. John's-wort may also experience browning as a result of overwatering. Underwatering is far less likely for your Matted St. John's-wort 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.
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How should I water my Matted St. John's-wort through the seasons?
You can expect your Matted St. John's-wort’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 Matted St. John's-wort, at times increasing to about three times per week. This is especially true of Matted St. John's-wort 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 Matted St. John's-wort 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.
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How should I water my Matted St. John's-wort at different growth stages?
Matted St. John's-wort 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 Matted St. John's-wort as a seed. While the seed germinates, you should plant to give more water than your Matted St. John's-wort will need later in life, watering often enough to maintain consistent soil moisture. After a few weeks, your Matted St. John's-wort 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.
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What's the difference between watering Matted St. John's-wort indoors and outdoors?
There are several reasons why most Matted St. John's-wort grow outdoors rather than indoors. The first is that these plants typically grow to tall. The second reason is that Matted St. John's-wort 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 Matted St. John's-wort 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.
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Every week
Matted St. John's-wort originates from regions with seasonal climates, preferring evenly moist soil. Ensure to water only when necessary to prevent overwatering, and always check soil moisture beforehand.
Learn More
Lighting
Full sun
Matted St. John's-wort thrives in areas where the sun frequently shines throughout the day and is capable of adapting to regions where sunshine is occasionally obscured by clouds. Originating from an environment rich in sunlight, it flourishes during all growth stages provided it receives ample light. However, too much or too little can negatively affect its vigorous growth.
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Matted St. John's-wort
Matted St. John's-wort
Matted St. John's-wort
Matted St. John's-wort
Matted St. John's-wort
Matted St. John's-wort
Add to My Garden
Matted St. John's-wort
Hypericum japonicum
Also known as: Japanese St. John's wort
Matted St. John's-wort (Hypericum japonicum) is a widespread wildflower that occurs in a large variety of mainly damp tropical habitats from rice fields to grasslands. While it isn't a common ornamental species, its dense and compact growth forms make it a good candidate for ground cover. Its small yellow flowers offer up to six months of garden interest.
Planting Time
Planting Time
Spring
plant_info

More Info

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Find your perfect green friends.
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distribution

Distribution Map

Habitat

Wet places in lowland, rice fields, ditches, marshes, grasslands, waste places, bog garden

Map

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Native
Cultivated
Invasive
Potentially invasive
Exotic
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question

Questions About Matted St. John's-wort

Watering Watering Watering
Sunlight Sunlight Sunlight
What is the best way to water my Matted St. John's-wort?
more
What should I do if I water my Matted St. John's-wort too much or too little?
more
How often should I water my Matted St. John's-wort?
more
How much water does my Matted St. John's-wort need?
more
How can I tell if i'm watering my Matted St. John's-wort enough?
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Essentials
Matted St. John's-wort originates from regions with seasonal climates, preferring evenly moist soil. Ensure to water only when necessary to prevent overwatering, and always check soil moisture beforehand.
Watering check today
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Spring
Summer
Autumn
Winter
Morning
Noonday
Evening
Morning watering can reduce the risk of fungal growth.
Requirements
Smart Seasonal Watering
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Seedling
Every 3 days
Growing
Every 5 days
Flowering
Every 3 days
Fruiting
Every 4 days
Calculated based on: Chicago / March
Amount and Approach
Watering from the soil
1. Gradually pour water to the soil from above.
2. Stop watering your plant once water begins to flow out of the drainage holes in the pot.
3. Allow it to rest for 1 minute, then discard any water remaining in the tray, making sure your plant is not sitting in the water.
Avoid watering the leaves or flowers. Use a watering can with a long spout when watering to reduce bending and exertion, and ease your fatigue.
Watering from the bottom
1. Fill the tray with water, ensure that the soil makes contact with the water.
2. Let it rest for 10 minutes.
3. Drain excess water from the tray if the soil is uniformly damp.
4. Watering more to the tray if the soil remains dry.
5. Allow it to sit for an additional 20 minutes before draining any excess water.
Avoid watering the leaves or flowers. Use a watering can with a long spout when watering to reduce bending and exertion, and ease your fatigue.
Soaking the water
1. Select a location for soaking your plants, such as a tray or bathtub.
2. Pour a few centimeters of fresh water into the bottom of your chosen container.
3. Soaking your plant pots within the water, allowing them to absorb moisture for 1 hour.
4. Remove the plants from the water and let them dry.
Avoid watering the leaves or flowers. Use a watering can with a long spout when watering to reduce bending and exertion, and ease your fatigue.
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For Matted St. John's-wort, outdoor watering can be done using the method of sprinkling. It is a simple and direct approach. It involves pouring water onto the soil around the plant, allowing the water to naturally seep into the root zone. Typically, containers such as watering cans, buckets, or watering jugs are used for sprinkling. Depending on the size of the plant, usually, 1-2 gallons of water are required to ensure the soil around the roots is thoroughly moistened.
Important Symptoms
Overwatering
Matted St. John's-wort is more susceptible to developing disease symptoms when overwatered because it prefers a soil environment with moderate humidity. Symptoms of overwatering include yellowing leaves, brown or black spots, root rot...
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(Symptom details and solutions)
Brown or black spots
Excessive watering can damage the plant's root system, making it vulnerable to fungal infections. The plant may develop dark brown to black spots that spread upwards from the lower leaves which are usually the first to be affected.
Root rot
Excess water in the soil can lead to the growth of harmful fungi and bacteria, causing the roots to rot and eventually kill the plant.
Soft or mushy stems
Excess water can cause stems to become soft and mushy, as the cells become waterlogged and lose their structural integrity.
Increased susceptibility diseases
Overwatering plants may become more susceptible and diseases as their overall health declines, weakening their natural defenses.
Solutions
1. Adjust watering frequency based on seasons and soil dryness. Wait for soil to dry before watering.2. Increase soil aeration by loosening surface and gently stirring with a wooden stick or chopstick.3. Optimize environment with good ventilation and warmth to enhance water evaporation and prevent overwatering.
Underwatering
Matted St. John's-wort is more susceptible to plant health issues when lacking watering, as it can only tolerate short periods of drought. Symptoms of dehydration include wilting, leaf curling, yellowing leaves...
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(Symptom details and solutions)
Wilting
Due to the dry soil and insufficient water absorption by the roots, the leaves of the plant will appear limp, droopy, and lose vitality.
Leaf curling
Leaves may curl inward or downward as they attempt to conserve water and minimize water loss through transpiration.
Increased susceptibility to pests and diseases
Underwatered plants may become more susceptible to pests and diseases as their overall health declines, weakening their natural defenses.
Dying plant
If underwatering continues for an extended period, the plant may ultimately die as a result of severe water stress and an inability to carry out essential functions.
Solutions
1. Thoroughly saturate soil with slow ring watering to ensure uniform and sufficient moisture for plants. 2. Increase air humidity with water trays or misting to slow leaf water evaporation. 3. Watering according to the recommended frequency.Adjust watering frequency based on seasons and soil dryness.
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Lighting
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Requirements
Full sun
Ideal
Above 6 hours sunlight
Partial sun
Tolerance
About 3-6 hours sunlight
Watch how sunlight gracefully moves through your garden, and choose spots that provide the perfect balance of light and shade for your plants, ensuring their happiness.
Essentials
Matted St. John's-wort thrives in areas where the sun frequently shines throughout the day and is capable of adapting to regions where sunshine is occasionally obscured by clouds. Originating from an environment rich in sunlight, it flourishes during all growth stages provided it receives ample light. However, too much or too little can negatively affect its vigorous growth.
Preferred
Tolerable
Unsuitable
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Artificial lighting
Indoor plants require adequate lighting for optimal growth. When natural sunlight is insufficient, particularly in winter or in less sunny spaces, artificial lights offer a vital solution, promoting faster, healthier growth.
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Indoor plants require adequate lighting for optimal growth. When natural sunlight is insufficient, particularly in winter or in less sunny spaces, artificial lights offer a vital solution, promoting faster, healthier growth.
1. Choose the right type of artificial light: LED lights are a popular choice for indoor plant lighting because they can be customized to provide the specific wavelengths of light that your plants need.
Full sun plants need 30-50W/sq ft of artificial light, partial sun plants need 20-30W/sq ft, and full shade plants need 10-20W/sq ft.
2. Determine the appropriate distance: Place the light source 12-36 inches above the plant to mimic natural sunlight.
3. Determine the duration: Mimic the length of natural daylight hours for your plant species. most plants need 8-12 hours of light per day.
Important Symptoms
Insufficient light
Matted St. John's-wort, a plant that thrives in full sunlight, is commonly grown outdoors with ample sunlight. When cultivated indoors with inadequate light, it may exhibit subtle symptoms of light deficiency.
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(Symptom details and solutions)
Small leaves
New leaves may grow smaller in size compared to the previous ones once they have matured.
Leggy or sparse growth
The spaces between leaves or stems of your Matted St. John's-wort may become longer, resulting in a thin and stretched-out appearance. This can make the plant look sparse and weak, and it may easily break or lean due to its own weight.
Faster leaf drop
When plants are exposed to low light conditions, they tend to shed older leaves early to conserve resources. Within a limited time, these resources can be utilized to grow new leaves until the plant's energy reserves are depleted.
Slower or no new growth
Matted St. John's-wort enters a survival mode when light conditions are poor, which leads to a halt in leaf production. As a result, the plant's growth becomes delayed or stops altogether.
Lighter-colored new leaves
Insufficient sunlight can cause leaves to develop irregular color patterns or appear pale. This indicates a lack of chlorophyll and essential nutrients.
Solutions
1. To ensure optimal growth, gradually move plants to a sunnier location each week, until they receive at least 6 hours of direct sunlight daily. Use a south-facing window and keep curtains open during the day for maximum sunlight exposure and nutrient accumulation.2. To provide additional light for your plant, consider using artificial light if it's large or not easily movable. Keep a desk or ceiling lamp on for at least 8 hours daily, or invest in professional plant grow lights for ample light.
Excessive light
Matted St. John's-wort thrives in full sun exposure and can tolerate intense sunlight. With their remarkable resilience, symptoms of sunburn may not be easily visible, as they rarely suffer from it.
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(Symptom details and solutions)
Chlorosis
Chlorosis is a condition where the plant's leaves lose their green color and turn yellow. This is due to the breakdown of chlorophyll from excessive sunlight, which negatively affects the plant's ability to photosynthesize.
Sunscald
Sunscald occurs when the plant's leaves or stems are damaged by intense sunlight exposure. It appears as pale, bleached, or necrotic areas on the plant tissue and can reduce the plant's overall health.
Leaf Curling
Leaf curling is a symptom where leaves curl or twist under extreme sunlight conditions. This is a defense mechanism used by the plant to reduce its surface area exposed to sunlight, minimizing water loss and damage.
Wilting
Wilting occurs when a plant loses turgor pressure and its leaves and stems begin to droop. Overexposure to sunlight can cause wilting by increasing the plant's water loss through transpiration, making it difficult for the plant to maintain adequate hydration.
Leaf Scorching
Leaf scorching is a symptom characterized by the appearance of brown, dry, and crispy edges or patches on leaves due to excessive sunlight. This can lead to a reduction in photosynthetic capacity and overall plant health.
Solutions
1. Move your plant to the optimal position where it can receive abundant sunlight but also have some shade. An east-facing window is an ideal choice as the morning sunlight is gentler. This way, your plant can enjoy ample sunlight while reducing the risk of sunburn.2. It is recommended to trim off any completely dehydrated or withered parts of the plant.
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