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Blue australian rosemary
Westringia 'Wynyabbie Gem'
Blue australian rosemary is a cross between W. fruticosa and W. eremicola, and is taller than the first parent and denser than the second. Its scientific name Westringia 'Wynyabbie Gem' comes from the place it was developed, Wynyabbie Nursery in Jindalee, Australia. Despite its tropical origin this plant is frost hardy and also resistant to drought. It’s green gray leaves offer year-round garden interest.
Care Guide for Blue australian rosemary
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Blue australian rosemary
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Key Facts About Blue australian rosemary
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Attributes of Blue australian rosemary
Lifespan
Perennial
Plant Type
Shrub
Leaf type
Evergreen
Scientific Classification of Blue australian rosemary
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Common Pests & Diseases About Blue australian rosemary
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Common issues for Blue australian rosemary based on 10 million real cases
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Dieback
There are several possible causes for dieback.
Solutions: There are a few things to try when dieback becomes apparent: Fertilize and water the plants - these two steps, along with judicious pruning, can help reduce the stress on the root system and encourage renewed vigor Have an arborist check to see if plant roots are girdling Test soil pH and adjust accordingly Remove and destroy infected twigs and branches
Nutrient deficiencies
A lack of nutrients will cause a widespread yellowing of the leaves. The yellowing may begin at the base or top of the plant.
Solutions: There are several easy ways to remedy the nutrient deficiencies in soils. Use a water-soluble fertilizer. Fertilizers will include most or all of the macro and micro-nutrients the plants need to thrive. Adding some fertilizer to the soil will make those nutrients available and can combat deficiencies. Regularly apply organic fertilizer pellets. Organic fertilizers such as animal manures and bonemeal can supply plants with all the nutrients that they need to grow strong and healthy. Apply compost. Though not as finely tuned as artificial fertilizer, compost can nevertheless be rich in important nutrients and should be applied to the soil regularly. Apply nutrients via foliar application. In addition to supplementing the soil with nutrients, foliar fertilizer can be applied directly to the plant's leaves. Nutrients offered via foliar application are often taken up even quicker than those put in the soil, so the foliar application can be great for swiftly addressing specific deficiencies.
Petal blight
Bacterial infections can cause flowers to become soft and rotten.
Solutions: Like other fungal diseases, the progression of petal blight is extremely difficult to stop and impossible to reverse once it infects a plant. The best course of action is to remove all damaged flowers immediately and dispose of them entirely. Do not put them in the compost pile, where spores could grow and spread.
Mealybugs
Mealybugs look like powdery white bumps about 1 to 2 mm across. They suck at the plant's sap.
Solutions: Mealybugs are not difficult to control once they are seen. If the gardener is playing close attention they can be dealt with before becoming established. Dip a cotton swab in alcohol and use it to apply alcohol to individual mealybugs. Avoid getting too much alcohol on plants as it will damage them. Rub off mealybugs using a washcloth or your fingers. Use a hose to spray these pests off of your plants. Close examination of the plant on a regular basis is the best weapon against infestation. For severe cases: - Spray entire plant with insecticidal soap or neem oil. Avoid spraying on sunny days and make sure to make contact with the mealybugs. Introduce or promote beneficial insects to the garden that eat mealybugs. Some beneficial insects include parasitic wasps, lady beetles, lacewings, and minute pirate bugs, but the most effective predator is the mealybug destroyer. For a chemical solution, spray a product that contains dinotefuran. Remove and discard heavily-infected plants.
Dieback
There are several possible causes for dieback.
Overview
Dealing with dieback in plants can be tricky, in part because this is both the name of a disease itself and a common symptom of many other types of diseases. Dieback can be characterized by the progressive, gradual death of shoots, twigs, roots, and branches, generally starting first at the tips.
In many cases, dieback is caused by fungi or bacteria. These pathogens can produce cankers, wilts, stem or root rots, and even anthracnose, but the most common symptom, of course, is that various plant parts (or the entire plant) will begin to die back.
Symptom Analysis
The symptoms of dieback can be gradual or slightly more abrupt. Usually, however, they are slow in developing and tend to be uniform among the various parts of a plant.
Some plants may have more localized symptoms, with all twigs affected or all branches affected but not the rest of the plant. Some potential symptoms include:
- Dead or dying branches and twigs
- Dieback that starts in the top of a plant and progresses downward (though it can start lower, especially for conifers)
- A delayed flush of growth in the spring
- Leaf margins become scorched
- Pale green or yellow leaves
- Leaves that are small or otherwise distorted
- Early leaf drop
- Reduced growth of twigs and stems
- Thinning of crown foliage
- Production of suckers on trunk and branches
- Premature fall coloration (in tree species like birch, sweetgum, maple, oak, ash, etc)
The symptoms of dieback can occur within just one season or become worse each and every year.
Disease Cause
There are several types of dieback, each of which has a different cause with which it is associated.
"dieback" as a standalone issue, including the condition known as Staghead, is caused by fungal or bacterial infections. Staghead is a slow dieback that occurs on the upper branches of a tree, named as such because the dead limbs look much like the head of a stag.
Other causes of dieback symptoms include:
- Cankers or wilts
- Stem or root rots
- Nematodes
- Stem or root boring insects
- Pavement being placed over root systems
- Winter injury from cold
- Salt damage
- Lack of moisture (or excess of moisture)
- Lack of an essential nutrient or element
Trees and shrubs that are attacked by insects, exposed to extremely high or low temperatures, or experience severe and frequent fluctuations in soil moisture are the most likely to suffer from dieback. These stress factors alone or in combination with each other can reduce leaf and shoot growth, and progress into death of twigs and branches.
Although any of these issues can lead to dieback, the most serious consequences tend to occur when the roots of a plant are damaged. Similarly, trees and shrubs that are planted improperly or in unfavorable locations are more likely to develop this condition.
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Nutrient deficiencies
A lack of nutrients will cause a widespread yellowing of the leaves. The yellowing may begin at the base or top of the plant.
Overview
Nutrient deficiencies can be seen in many different ways on plants. Basically, the lack of nutrients will inhibit plant growth, produce weak stems and leaves, and leave plants open to infection from pests and diseases. Plants use the nutrients from the soil to help them with photosynthesis. This, in turn, produces healthy plant growth. Plants that lack adequate amounts of nutrients will look lackluster and unhealthy. Eventually, if this is not addressed, it will cause the plants to die. The most important nutrients that plants need are nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur. Additionally, plants require small amounts of micronutrients such as iron, boron, manganese, zinc, copper, and molybdenum.
Symptom Analysis
A common sign that plants are experiencing nutrient deficiencies is the yellowing of leaves. This may be an overall yellowing or leaves that are yellow but still have green veins. These leaves will eventually brown off and die.
Another sign is the loss of plant vigor. The plants may not be growing as well as they should or their growth may be stunted.
Below are some common symptoms that appear when plants are lacking in nutrients.
Nitrogen (N): Inner, older leaves yellow first. If the deficiency is severe, yellowing progresses outward to newer growth.
Potassium (K): Leaf edges may turn brown and crinkly, with a yellowing layer forming just inside of the edge. Older leaves tend to be impacted first.
Phosphorus (P): Lack of vigorous growth. Plants will appear stunted.
Zinc (Zn): Yellowing tends to occur first at the base of the leaf.
Copper (Cu): Newer leaves begin to yellow first, with older leaves yellowing only if the deficiency becomes severe.
Boron (B): Newer leaves are impacted first. Foliage may also become particularly brittle in cases of boron deficiency.
Disease Cause
There are several factors that can lead to nutrient deficiencies, a situation where plants are not receiving the nutrients that they need. This could be because they are planted in nutrient-deficient soils, or that the soil's pH is too high or low. Incorrect soil pH can lock up certain nutrients, thus making them unavailable to plants. Lack of soil moisture can also be a problem, because plants need water to be able to absorb the nutrients from the soil.
Continue reading in our app - it's better
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Scan the QR code with your phone camera to download the app
Petal blight
Bacterial infections can cause flowers to become soft and rotten.
Overview
Petal blight, sometimes called flower blight, is a fungal disease that only affects the blooms of some ornamental flowering plants. As the infection progresses, it destroys the flower, yet it never damages the vegetative or green parts of the plant.
When flowers are infected, the symptoms look similar to Botrytis blight, but Botrytis also infects dead or dormant vegetative tissue.
The disease was first discovered in Japanese plants in 1919 and in the US in the late 1930s. Presently it is also found in New Zealand, Australia, and parts of Europe. Unfortunately, no plants have high resistance to petal blight, but specific cultivars are more susceptible than others, particularly species with double blooms.
Petal blight infection rates are high when temperatures are mild to warm (optimum temperatures are 15 to 21 ℃) and the weather is misty or rainy.
Overall, petal blight is an aesthetic problem that ruins blossoms. The disease is not harmful to the long-term health of the plant.
Symptom Analysis
The severity of the symptoms varies, depending upon the species of plant infected. Signs of petal blight are commonly seen on the blooms just after they open.
- Pallid spots on colored petals.
- Brown spots on white petals.
- Browning around the petal edges.
- Small spots look water-soaked.
- Spots rapidly enlarge and merge.
- Flowers become limp.
- The entire flower turns light brown, but does not crumble.
- Flowers become slimy at first and then take on a leathery texture.
- A ring of white or gray mycelium can be seen at the base of the petals.
Disease Cause
Petal blight is caused by several different fungi, with each type infecting specific plants. Ovulinia azalea infects azaleas species and cultivars, and rhododendrons. Ciborinia camelliae infects camellia cultivars.
Shortly after blooming, the fungus infects the base of the flowers by the calyx. The fungus produces cell wall-degrading enzymes that destroy flowers within a couple of days. When the flowers fall to the ground, the fungus' hard fruiting bodies fall to the soil as well, overwintering until the following spring.
When temperatures hit the optimum range the following season, spores are transmitted by insects or can spread on wind currents up to about 12 miles. Once in the soil, the pathogen can be active for three to five years.
Continue reading in our app - it's better
A database of 400000+ plants and unlimited guides at your fingertips...
Scan the QR code with your phone camera to download the app
Mealybugs
Mealybugs look like powdery white bumps about 1 to 2 mm across. They suck at the plant's sap.
Overview
Mealybugs are sap-sucking insects of the Pseudococcidae family. They produce a white waxy secretion that makes them look like a dusting of flour. They thrive in warm moist conditions and so are often found on houseplants or in greenhouses, where they tend to hide in crevices such as leaf nodules and at the base of stems. Once in position they don't move and instead focus on sucking sap from the host plant.
Symptom Analysis
These creatures are quite easy to identify but because they hide in crevices, the gardener will need to be looking for them.
Small white woolly-looking dots will be seen in leaf axis and beneath leaves. Initially it may appear as though the plant has gathered patches of a light flour-like dust or bits of cotton fluff.
Initial infestations tend to be quite minor but left unaddressed, these creatures breed rapidly and can threaten the health of the plant. Severely infested plants will exhibit yellowing leaves that lack normal texture and become soft.
Solutions
Mealybugs are not difficult to control once they are seen. If the gardener is playing close attention they can be dealt with before becoming established.
- Dip a cotton swab in alcohol and use it to apply alcohol to individual mealybugs. Avoid getting too much alcohol on plants as it will damage them.
- Rub off mealybugs using a washcloth or your fingers.
- Use a hose to spray these pests off of your plants.
- Close examination of the plant on a regular basis is the best weapon against infestation.
For severe cases: - Spray entire plant with insecticidal soap or neem oil. Avoid spraying on sunny days and make sure to make contact with the mealybugs.
- Introduce or promote beneficial insects to the garden that eat mealybugs. Some beneficial insects include parasitic wasps, lady beetles, lacewings, and minute pirate bugs, but the most effective predator is the mealybug destroyer.
- For a chemical solution, spray a product that contains dinotefuran.
- Remove and discard heavily-infected plants.
Continue reading in our app - it's better
A database of 400000+ plants and unlimited guides at your fingertips...
Scan the QR code with your phone camera to download the app
Continue reading in our app - it's better
A database of 400000+ plants and unlimited guides at your fingertips...
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About
Care Guide
More Info
Pests & Diseases
Blue australian rosemary
Westringia 'Wynyabbie Gem'
Blue australian rosemary is a cross between W. fruticosa and W. eremicola, and is taller than the first parent and denser than the second. Its scientific name Westringia 'Wynyabbie Gem' comes from the place it was developed, Wynyabbie Nursery in Jindalee, Australia. Despite its tropical origin this plant is frost hardy and also resistant to drought. It’s green gray leaves offer year-round garden interest.
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Care Guide for Blue australian rosemary
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Find the best spots for them to optimize their health, simply using your phone.
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Key Facts About Blue australian rosemary
Feedback
Attributes of Blue australian rosemary
Lifespan
Perennial
Plant Type
Shrub
Leaf type
Evergreen
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Scientific Classification of Blue australian rosemary
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Common Pests & Diseases About Blue australian rosemary
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Common issues for Blue australian rosemary based on 10 million real cases
Plant disease auto-diagnose & prevention
AI-powered plant doctor helps you diagnose plant problems in seconds.
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Dieback
There are several possible causes for dieback.
Solutions: There are a few things to try when dieback becomes apparent: Fertilize and water the plants - these two steps, along with judicious pruning, can help reduce the stress on the root system and encourage renewed vigor Have an arborist check to see if plant roots are girdling Test soil pH and adjust accordingly Remove and destroy infected twigs and branches
Learn More About the Dieback ![more]()
Nutrient deficiencies
A lack of nutrients will cause a widespread yellowing of the leaves. The yellowing may begin at the base or top of the plant.
Solutions: There are several easy ways to remedy the nutrient deficiencies in soils. Use a water-soluble fertilizer. Fertilizers will include most or all of the macro and micro-nutrients the plants need to thrive. Adding some fertilizer to the soil will make those nutrients available and can combat deficiencies. Regularly apply organic fertilizer pellets. Organic fertilizers such as animal manures and bonemeal can supply plants with all the nutrients that they need to grow strong and healthy. Apply compost. Though not as finely tuned as artificial fertilizer, compost can nevertheless be rich in important nutrients and should be applied to the soil regularly. Apply nutrients via foliar application. In addition to supplementing the soil with nutrients, foliar fertilizer can be applied directly to the plant's leaves. Nutrients offered via foliar application are often taken up even quicker than those put in the soil, so the foliar application can be great for swiftly addressing specific deficiencies.
Learn More About the Nutrient deficiencies ![more]()
Petal blight
Bacterial infections can cause flowers to become soft and rotten.
Solutions: Like other fungal diseases, the progression of petal blight is extremely difficult to stop and impossible to reverse once it infects a plant. The best course of action is to remove all damaged flowers immediately and dispose of them entirely. Do not put them in the compost pile, where spores could grow and spread.
Learn More About the Petal blight ![more]()
Mealybugs
Mealybugs look like powdery white bumps about 1 to 2 mm across. They suck at the plant's sap.
Solutions: Mealybugs are not difficult to control once they are seen. If the gardener is playing close attention they can be dealt with before becoming established. Dip a cotton swab in alcohol and use it to apply alcohol to individual mealybugs. Avoid getting too much alcohol on plants as it will damage them. Rub off mealybugs using a washcloth or your fingers. Use a hose to spray these pests off of your plants. Close examination of the plant on a regular basis is the best weapon against infestation. For severe cases: - Spray entire plant with insecticidal soap or neem oil. Avoid spraying on sunny days and make sure to make contact with the mealybugs. Introduce or promote beneficial insects to the garden that eat mealybugs. Some beneficial insects include parasitic wasps, lady beetles, lacewings, and minute pirate bugs, but the most effective predator is the mealybug destroyer. For a chemical solution, spray a product that contains dinotefuran. Remove and discard heavily-infected plants.
Learn More About the Mealybugs ![more]()
Dieback
There are several possible causes for dieback.
Overview
Dealing with dieback in plants can be tricky, in part because this is both the name of a disease itself and a common symptom of many other types of diseases. Dieback can be characterized by the progressive, gradual death of shoots, twigs, roots, and branches, generally starting first at the tips.
In many cases, dieback is caused by fungi or bacteria. These pathogens can produce cankers, wilts, stem or root rots, and even anthracnose, but the most common symptom, of course, is that various plant parts (or the entire plant) will begin to die back.
Symptom Analysis
The symptoms of dieback can be gradual or slightly more abrupt. Usually, however, they are slow in developing and tend to be uniform among the various parts of a plant.
Some plants may have more localized symptoms, with all twigs affected or all branches affected but not the rest of the plant. Some potential symptoms include:
- Dead or dying branches and twigs
- Dieback that starts in the top of a plant and progresses downward (though it can start lower, especially for conifers)
- A delayed flush of growth in the spring
- Leaf margins become scorched
- Pale green or yellow leaves
- Leaves that are small or otherwise distorted
- Early leaf drop
- Reduced growth of twigs and stems
- Thinning of crown foliage
- Production of suckers on trunk and branches
- Premature fall coloration (in tree species like birch, sweetgum, maple, oak, ash, etc)
The symptoms of dieback can occur within just one season or become worse each and every year.
Disease Cause
There are several types of dieback, each of which has a different cause with which it is associated.
"dieback" as a standalone issue, including the condition known as Staghead, is caused by fungal or bacterial infections. Staghead is a slow dieback that occurs on the upper branches of a tree, named as such because the dead limbs look much like the head of a stag.
Other causes of dieback symptoms include:
- Cankers or wilts
- Stem or root rots
- Nematodes
- Stem or root boring insects
- Pavement being placed over root systems
- Winter injury from cold
- Salt damage
- Lack of moisture (or excess of moisture)
- Lack of an essential nutrient or element
Trees and shrubs that are attacked by insects, exposed to extremely high or low temperatures, or experience severe and frequent fluctuations in soil moisture are the most likely to suffer from dieback. These stress factors alone or in combination with each other can reduce leaf and shoot growth, and progress into death of twigs and branches.
Although any of these issues can lead to dieback, the most serious consequences tend to occur when the roots of a plant are damaged. Similarly, trees and shrubs that are planted improperly or in unfavorable locations are more likely to develop this condition.
Solutions
There are a few things to try when dieback becomes apparent:
- Fertilize and water the plants - these two steps, along with judicious pruning, can help reduce the stress on the root system and encourage renewed vigor
- Have an arborist check to see if plant roots are girdling
- Test soil pH and adjust accordingly
- Remove and destroy infected twigs and branches
Prevention
The best way to prevent dieback is to match the plant to the site. Make sure the conditions provided for a new planting match its needs.
- Plant properly in deep, fertile well-draining soil
- Make sure plant roots won’t be confined when the plant reaches its mature size
- Avoid changes to the growing site
- If soil compaction might be an issue, apply a few inches of wood chips and eliminate traffic over the root area
- Fertilize and water appropriately
It is also important to avoid potential infection with pathogens that can cause dieback:
- Avoid binding or wounding the roots and trunk whenever possible
- Avoid excessive pruning
- Disinfect all tools before working with plants to reduce the spread of disease
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unlimited guides at your fingertips...
unlimited guides at your fingertips...
Nutrient deficiencies
A lack of nutrients will cause a widespread yellowing of the leaves. The yellowing may begin at the base or top of the plant.
Overview
Nutrient deficiencies can be seen in many different ways on plants. Basically, the lack of nutrients will inhibit plant growth, produce weak stems and leaves, and leave plants open to infection from pests and diseases. Plants use the nutrients from the soil to help them with photosynthesis. This, in turn, produces healthy plant growth. Plants that lack adequate amounts of nutrients will look lackluster and unhealthy. Eventually, if this is not addressed, it will cause the plants to die. The most important nutrients that plants need are nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur. Additionally, plants require small amounts of micronutrients such as iron, boron, manganese, zinc, copper, and molybdenum.
Symptom Analysis
A common sign that plants are experiencing nutrient deficiencies is the yellowing of leaves. This may be an overall yellowing or leaves that are yellow but still have green veins. These leaves will eventually brown off and die.
Another sign is the loss of plant vigor. The plants may not be growing as well as they should or their growth may be stunted.
Below are some common symptoms that appear when plants are lacking in nutrients.
Nitrogen (N): Inner, older leaves yellow first. If the deficiency is severe, yellowing progresses outward to newer growth.
Potassium (K): Leaf edges may turn brown and crinkly, with a yellowing layer forming just inside of the edge. Older leaves tend to be impacted first.
Phosphorus (P): Lack of vigorous growth. Plants will appear stunted.
Zinc (Zn): Yellowing tends to occur first at the base of the leaf.
Copper (Cu): Newer leaves begin to yellow first, with older leaves yellowing only if the deficiency becomes severe.
Boron (B): Newer leaves are impacted first. Foliage may also become particularly brittle in cases of boron deficiency.
Disease Cause
There are several factors that can lead to nutrient deficiencies, a situation where plants are not receiving the nutrients that they need. This could be because they are planted in nutrient-deficient soils, or that the soil's pH is too high or low. Incorrect soil pH can lock up certain nutrients, thus making them unavailable to plants. Lack of soil moisture can also be a problem, because plants need water to be able to absorb the nutrients from the soil.
Solutions
There are several easy ways to remedy the nutrient deficiencies in soils.
- Use a water-soluble fertilizer. Fertilizers will include most or all of the macro and micro-nutrients the plants need to thrive. Adding some fertilizer to the soil will make those nutrients available and can combat deficiencies.
- Regularly apply organic fertilizer pellets. Organic fertilizers such as animal manures and bonemeal can supply plants with all the nutrients that they need to grow strong and healthy.
- Apply compost. Though not as finely tuned as artificial fertilizer, compost can nevertheless be rich in important nutrients and should be applied to the soil regularly.
- Apply nutrients via foliar application. In addition to supplementing the soil with nutrients, foliar fertilizer can be applied directly to the plant's leaves. Nutrients offered via foliar application are often taken up even quicker than those put in the soil, so the foliar application can be great for swiftly addressing specific deficiencies.
Prevention
There are several easy ways to prevent nutrient deficiencies in plants.
- Regular fertilizing. Regular addition of fertilizer to the soil is one of the simplest and most effective ways to prevent deficiencies.
- Proper watering. Both over and under watering can adversely impact a plant's roots, which in turn makes it harder for them to properly take up nutrients.
- Testing the soil's pH. A soil's acidity or alkalinity will impact the degree to which certain nutrients are available to be taken up by plants. Knowing the soil's pH means it can be amended to suit the needs of the individual plants.
Continue reading in our app - it's better
A database of 400000+ plants
unlimited guides at your fingertips...
unlimited guides at your fingertips...
Petal blight
Bacterial infections can cause flowers to become soft and rotten.
Overview
Petal blight, sometimes called flower blight, is a fungal disease that only affects the blooms of some ornamental flowering plants. As the infection progresses, it destroys the flower, yet it never damages the vegetative or green parts of the plant.
When flowers are infected, the symptoms look similar to Botrytis blight, but Botrytis also infects dead or dormant vegetative tissue.
The disease was first discovered in Japanese plants in 1919 and in the US in the late 1930s. Presently it is also found in New Zealand, Australia, and parts of Europe. Unfortunately, no plants have high resistance to petal blight, but specific cultivars are more susceptible than others, particularly species with double blooms.
Petal blight infection rates are high when temperatures are mild to warm (optimum temperatures are 15 to 21 ℃) and the weather is misty or rainy.
Overall, petal blight is an aesthetic problem that ruins blossoms. The disease is not harmful to the long-term health of the plant.
Symptom Analysis
The severity of the symptoms varies, depending upon the species of plant infected. Signs of petal blight are commonly seen on the blooms just after they open.
- Pallid spots on colored petals.
- Brown spots on white petals.
- Browning around the petal edges.
- Small spots look water-soaked.
- Spots rapidly enlarge and merge.
- Flowers become limp.
- The entire flower turns light brown, but does not crumble.
- Flowers become slimy at first and then take on a leathery texture.
- A ring of white or gray mycelium can be seen at the base of the petals.
Disease Cause
Petal blight is caused by several different fungi, with each type infecting specific plants. Ovulinia azalea infects azaleas species and cultivars, and rhododendrons. Ciborinia camelliae infects camellia cultivars.
Shortly after blooming, the fungus infects the base of the flowers by the calyx. The fungus produces cell wall-degrading enzymes that destroy flowers within a couple of days. When the flowers fall to the ground, the fungus' hard fruiting bodies fall to the soil as well, overwintering until the following spring.
When temperatures hit the optimum range the following season, spores are transmitted by insects or can spread on wind currents up to about 12 miles. Once in the soil, the pathogen can be active for three to five years.
Solutions
Like other fungal diseases, the progression of petal blight is extremely difficult to stop and impossible to reverse once it infects a plant. The best course of action is to remove all damaged flowers immediately and dispose of them entirely. Do not put them in the compost pile, where spores could grow and spread.
Prevention
- Apply a preventative dose of fungicide as soon as blooms start to show color on the plant. The preventative can be applied as a soil drench or directly to the flowers on the plant.
- Avoid overhead watering during blooming.
- Remove any leaf litter and dead flowers at the end of the season.
- Cover the ground under infected plants with 4” of fresh organic mulch before winter, taking care not to disturb the infected soil.
- Buy bare-root specimens when available.
- When potted plants are purchased, remove the top layer of potting soil and replace it with fresh mulch.
- Plant cultivars that bloom early in the season before the temperatures get high enough for petal blight pathogens to be spreading.
Continue reading in our app - it's better
A database of 400000+ plants
unlimited guides at your fingertips...
unlimited guides at your fingertips...
Mealybugs
Mealybugs look like powdery white bumps about 1 to 2 mm across. They suck at the plant's sap.
Overview
Mealybugs are sap-sucking insects of the Pseudococcidae family. They produce a white waxy secretion that makes them look like a dusting of flour. They thrive in warm moist conditions and so are often found on houseplants or in greenhouses, where they tend to hide in crevices such as leaf nodules and at the base of stems. Once in position they don't move and instead focus on sucking sap from the host plant.
Symptom Analysis
These creatures are quite easy to identify but because they hide in crevices, the gardener will need to be looking for them.
Small white woolly-looking dots will be seen in leaf axis and beneath leaves. Initially it may appear as though the plant has gathered patches of a light flour-like dust or bits of cotton fluff.
Initial infestations tend to be quite minor but left unaddressed, these creatures breed rapidly and can threaten the health of the plant. Severely infested plants will exhibit yellowing leaves that lack normal texture and become soft.
Solutions
Mealybugs are not difficult to control once they are seen. If the gardener is playing close attention they can be dealt with before becoming established.
- Dip a cotton swab in alcohol and use it to apply alcohol to individual mealybugs. Avoid getting too much alcohol on plants as it will damage them.
- Rub off mealybugs using a washcloth or your fingers.
- Use a hose to spray these pests off of your plants.
- Close examination of the plant on a regular basis is the best weapon against infestation.
For severe cases: - Spray entire plant with insecticidal soap or neem oil. Avoid spraying on sunny days and make sure to make contact with the mealybugs.
- Introduce or promote beneficial insects to the garden that eat mealybugs. Some beneficial insects include parasitic wasps, lady beetles, lacewings, and minute pirate bugs, but the most effective predator is the mealybug destroyer.
- For a chemical solution, spray a product that contains dinotefuran.
- Remove and discard heavily-infected plants.
Prevention
Recommended steps for prevention, from most to least common, are as follows:
- Examine plants carefully before purchasing. Mealybugs are most commonly brought in on contaminated plants.
- Avoid overfeeding plants with nitrogen, as it makes them too tender and easy for the mealybugs to insert their sucking mouth parts into.
- Regularly check plants, pots, and tools for them. They are very easy to spot once the gardener knows what to look for and where to look.
- Keep plants in good health by properly fertilizing and irrigating.
- Avoid using insecticides that can kill beneficial insects. Neem tree oil and vegetable soaps are highly effective.
- Regular spraying or wiping with an insecticidal soap is a good deterrent and affords the gardener an opportunity to examine for any infestations.
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Your Ultimate Guide to Plants
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17,000 local species +400,000 global species studied
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Continue reading in our app - it's better
A database of 400000+ plants
unlimited guides at your fingertips...
unlimited guides at your fingertips...
