Brown Roses
I have 3 rose bushes that are next to each other. 2 of them look great! One of them not so much. As soon as they start opening...as soon as you can see color, the tips of the petals are brown. Then when the rose opens, it is big an pink with brown/nasty petal tips. Has anyone had this problem before??
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luis_pr
- Greener Thumb
- Posts: 824
- Joined: Sun Jul 05, 2009 8:31 am
- Location: Hurst, TX USA Zone 7b/8a
Hello, nicro. I have had a few instances of this problem and these are some of the things usually behind it:
* thrips: the larvae form of this pest sucks plant juices during this time of the year (Spring and early Summer) and causes the tips/edges of the petals to turn brown. To determine if you have thrips, use your hands to pull back all the petals in one of the flowers (one at a time). If you see small/tiny insects running around for cover, those are thrips. To control thrips, you can regularly spray the shrubs with the hose (hard). You can also release beneficial insects like lacewings, predatory mites, parasitic wasps, etc. Beneficial insects are normally available from organic minded stores or local nurseries at this time of the year. You can also use chemical or organic pesticides such as: Sunspray, Neem Oil, Avid, Bayer Advanced Garden Tree & Shrub Insect Control, etc. Please note that some chemical pesticides will kill beneficial insects causing an increase of other pests so use them only if the infestation is large.
Here is a picture of the damage thrips cause and pictures of some thrips:
https://images.search.yahoo.com/search/images?_adv_prop=image&fr=slv8-swat02&va=rose+thrips+in+roses
* rose balling is a common disorder in humid locales that some roses suffer from. This problem occurs when water tends to accumulate in the bloom due to high humidity levels in a -usually- part-shaded area. After a while, a grey fungus begins to develop causing the blooms to brown out and rot. Rose balling should be the diagnosis when the blooms stink a little, feel flimsy and/or papery and "fuse" together. Affected blooms should be pruned off and discarded in the trash, not the compost pile. If the branch shows signs of die back, prune back to healthy tissue. When done pruning, clean the pruners for a few minutes using a solution of 1 part bleach and 10 parts water.
There are some things that you can do to minimize the chance of rose balling: do not do overhead watering of roses; instead, water the soil early in the mornings; allow for air movement between the rose and other plants; choose an area that gets full sun; choose varieties that do not have very densely petalled blooms; transplant affected plants to a more sunny location (not practical always of course). Examples of roses that suffer from balling: old roses such as Alba, Auguste Renoir , Boule de Neige, etc. Examples of roses that resist it: Souvenir de St. Anne's, Gertrude Jekyll, hybrid teas, etc
Here is a picture of the damage that rose balling does courtesy of the BBC: https://www.gardenersworld.com/how-to/problem-solving/rose-bloom-balling/main.jpg
* heat stress: common in some newly planted dark bloom roses. The problem can be corrected by letting the plant harden off before planting it in full sun.
* Rotting: lack of good soil drainage can make the roots rot; consider using raised beds if your soil is clay and the soil drains poorly.
* Application of pesticides can sometimes also cause this type of reaction on the rose bush. Air will transport small drops of the pesticide to nearby plants so, for example, you could apply the pesticide away from the rose and still have the rose bush have what is called a phytotoxic reaction.
* Mineral deficiencies in the soil can also cause this problem. But this is rare and usually caused by too much chemical fertilizers and-or lack of calcium. I feed my roses organic products like cottonseed meal, alfalfa meal, blood meal, kelp meal and-or bone meal. Some of these products are available at HD and Lowes but the majority are found in organic minded stores and local nurseries.
Does that help you, nicro?
Luis
* thrips: the larvae form of this pest sucks plant juices during this time of the year (Spring and early Summer) and causes the tips/edges of the petals to turn brown. To determine if you have thrips, use your hands to pull back all the petals in one of the flowers (one at a time). If you see small/tiny insects running around for cover, those are thrips. To control thrips, you can regularly spray the shrubs with the hose (hard). You can also release beneficial insects like lacewings, predatory mites, parasitic wasps, etc. Beneficial insects are normally available from organic minded stores or local nurseries at this time of the year. You can also use chemical or organic pesticides such as: Sunspray, Neem Oil, Avid, Bayer Advanced Garden Tree & Shrub Insect Control, etc. Please note that some chemical pesticides will kill beneficial insects causing an increase of other pests so use them only if the infestation is large.
Here is a picture of the damage thrips cause and pictures of some thrips:
https://images.search.yahoo.com/search/images?_adv_prop=image&fr=slv8-swat02&va=rose+thrips+in+roses
* rose balling is a common disorder in humid locales that some roses suffer from. This problem occurs when water tends to accumulate in the bloom due to high humidity levels in a -usually- part-shaded area. After a while, a grey fungus begins to develop causing the blooms to brown out and rot. Rose balling should be the diagnosis when the blooms stink a little, feel flimsy and/or papery and "fuse" together. Affected blooms should be pruned off and discarded in the trash, not the compost pile. If the branch shows signs of die back, prune back to healthy tissue. When done pruning, clean the pruners for a few minutes using a solution of 1 part bleach and 10 parts water.
There are some things that you can do to minimize the chance of rose balling: do not do overhead watering of roses; instead, water the soil early in the mornings; allow for air movement between the rose and other plants; choose an area that gets full sun; choose varieties that do not have very densely petalled blooms; transplant affected plants to a more sunny location (not practical always of course). Examples of roses that suffer from balling: old roses such as Alba, Auguste Renoir , Boule de Neige, etc. Examples of roses that resist it: Souvenir de St. Anne's, Gertrude Jekyll, hybrid teas, etc
Here is a picture of the damage that rose balling does courtesy of the BBC: https://www.gardenersworld.com/how-to/problem-solving/rose-bloom-balling/main.jpg
* heat stress: common in some newly planted dark bloom roses. The problem can be corrected by letting the plant harden off before planting it in full sun.
* Rotting: lack of good soil drainage can make the roots rot; consider using raised beds if your soil is clay and the soil drains poorly.
* Application of pesticides can sometimes also cause this type of reaction on the rose bush. Air will transport small drops of the pesticide to nearby plants so, for example, you could apply the pesticide away from the rose and still have the rose bush have what is called a phytotoxic reaction.
* Mineral deficiencies in the soil can also cause this problem. But this is rare and usually caused by too much chemical fertilizers and-or lack of calcium. I feed my roses organic products like cottonseed meal, alfalfa meal, blood meal, kelp meal and-or bone meal. Some of these products are available at HD and Lowes but the majority are found in organic minded stores and local nurseries.
Does that help you, nicro?
Luis