New to Hydrangeas here only in my first year with the 2 I have. Something is eating holes in both of them and I have no clue what to use :( Is there anything that any of you guys can reccomend? I have tried Escar-Go which works great on my other plants but have had no luck.
TIA
Mel
Pesticides for Hydrangeas?
Could be earwigs, try some diamecious earth (spelling) . they crawl on it and it cuts them up and then they die, but has to be reapplied after a rain.
Jill
Are we talking a lot of holes or just a few? Leaves on the bottom or everywhere? Can you take a picture of the bush and a close up of one or two leaves?
Sometimes I do nothing. Like when just a few leaves develop fungal infections this time of the year (mid summer). One could apply fungicide but being so late in the year, the temps will take care of the problem.
Here are a couple of pics from today..
The other pic. These are both about a year old.
This message was edited Jul 29, 2007 4:10 PM
Hello, mellymass. You should also consider adult rose chafers (they look like scarab beetles), pests that feed many flowering plants whose leaves are often left skeletonized with veins and small amounts of tissue left behind. There are also some types of caterpillars that could be active in your zone this time of the year.
I guess that means I am not helping as you need to isolate the culprit before you can apply an insecticide or take some control measures. Short term and easy solutions: take a sample to your local nursery and ask them what insects are active right now that could be causing this damage. Show them a few photos or tale leaf samples in a seales transparent plastic envelope. Your local agriculture extension service & universities could also help.
When doing some researching on pests in my garden, I have monitored damage daily in order to tell when it is happening (day or evening). I next add some powder around the base of the plant to see if the pest leaves a trail. For example, caterpillars will hide under mulch and rocks and climb up the main trunk. Some hide under the leaves and others climb up the plant daily. They could therefore disturb the powder. Bt is very useful against those critters.
If the powder is not disturbed and damage continues, then an airborne pest or one which can jump from nearby plants could be the culprit. Again, it could be a night-time pest or a day-time pest so determining when damage occurs is important.
Earwigs for instance, like tender new growth, are nocturnal (active at night) and hide during the day in mulch, cracks, under pots, etc. The female likes to hide the eggs in protected places and will guard them until they hatch. Leaf damage is done by the mouthparts when chewing and not by the pinchers at the end of their tails. They can be controlled with insecticides containing carbaryl (Sevin) or spray a barrier around the plants with chlorpyriphos (Dursban). Remember to treat places where they may hide (under pots, flowerboxes, etc)
Rose chafers appear starting in June in the northern half of the country (approximately), like to concentrate on "a" single plant and have a short life (about 3 weeks). Even though its name is rose-related, they attack plants like rose, apple, crabapple, grape, cherry, strawberry, raspberry, hydrangea, peony, Virginia Creeper, hollyhock, ornamental plants and vegetables. The larvae/grubs live in the soil. You can protect plants with cheesecloth. The adults can be controlled with insecticides containing carbaryl (Sevin), methoxychlor or permethrin. The larvae can be controlled by plowing/harrowing to a depth of 3" as they are very sensitive to soil disturbances. There are granular insecticides available to control the larvae but I could not find the names (maybe a local nursery will have them).
But as I said at the start, you need to identify the culprit before applying any insecticide. The lack of success/progress with Escar-Go simply shows that the pest is not a slug or snail.
Good luck, mellynass.
Luis
Luis,
Thanks for the great advice. I will have to try to keep a closer eye on what could be causing the damage. While I was out yesterday I did find one of the culprits behind damage to my asiatic lilies it was the Lily Leaf Beetle. This guy wasnt shy kept munching away while I was checking it out.
Ha! Yes indeed. They are not shy sometimes!