Garner,

I think you're on the right track with neem on the powdery mildew. It just shows up this time of year. I would add that you should be carefully cutting out the affected leaves and throw them in the trash, not the compost bin. Lessen the spread as much as you can. The bindweed here is just covered in powdery mildew and is making a run for my good stuff.

I've heard that giving your plants, top and underside a really good spraying of water will knock down the spider mites. You may have to do that once or twice a day to keep them in check. If you're plantings are really close together you might be spreading the powdery mildew when you do that, though.

It's getting to be the time of year where I don't worry about it too much. The season is winding down.

Not much help, but know that you're not alone!

Barb

You can knock back spider mites with a soapy water spray - the current fad is using Dawn detergent, I use Dr. Bronners Peppermint soap.

Try a leaf or two first, leave it over night, to make sure you're not harming the plant.

Thanks for the tips! I'll give em a go!

Powdery mildew has been the bane of my pumpkin plants since June. It's all my fault, I know, because I planted them in a spot that was far more shady than I should have ever put them in. Plus the cool, wet weather only made things worse. Oh well... there's always next year. I always wind up with PM in late August-September on my squash and cucumbers, but to be honest, by this time most years, I'm quite ready to be done with them anyways (you can only eat zucchini so many nights in a row, and the freezer fills up quick).

I usually don't treat, I'm too lazy and too cheap. Although, if the PM is half as bad next year as it was this year, I have been looking into ways of dealing with it. I have been reading a lot of stories about milk being used pretty successfully. Though, whether or not it is true or simply stories, I don't know. You can give it try I suppose, I think the ratio was 1 part milk to 3 parts water, but you can do a quick google search of milk and powdery mildew to find out for sure.

I also read that powdery mildew is host-specific. Supposedly, there are countless strains, and all of them prey on certain plants. So, IF THAT IS TRUE it would mean that it will not spread amongst your different garden plants. So far, that seems to be holding out in my garden where my cucumbers, which are almost entirely white, run amongst tomatoes, basil, peppers, corn, onions, carrots, and the PM seems to be pretty happy sticking only to the cukes. Of course, I think after this year I'm going to have to wait a while before I plant cucurbits again.

I have felt that older plants are the vulnerable ones with PM. However, a problem "since June" suggests otherwise.

The space taken up by early cabbage is somewhat equivalent to a bush-type summer squash. Setting out a 2nd planting of zucchini in June should mean a fresh season of harvest at this time of year. Of course, if it isn't a bad year for mildew, the results can be a lot going to the compost pile.

Since I have had a bed of July-harvested shallots for years, that is another place with room mid-season. Usually, it is a location for cucumbers but there is zucchini in that bed this year. A late planting of cukes went in the sweet corn. ... along with radish, cilantro, dill ...

Late sowings of green beans are certainly possible in most places. Older plants sure can be infested by huge numbers of spider mites! One picking and then pulling the beans isn't a bad idea.

None of these ideas are of help to GarnerGarden. First, I should apologize but this is an edit and the forcing of GarnerGarden to read all this and come to the same conclusion has been done. Second, I don't mean to say that I harvest early cabbage in June. Rather, I start squash seeds in June and get the plants between the cabbages by the first week of July. Sometimes, I just sow the seeds in place at that time. When the cabbages are harvested, the squash can take over the space.
Steve

This post was edited by digit on Fri, Sep 5, 14 at 14:35

Well....I'll be honest here... I killed my first squash earlier this year and then replaced it a bit late in the season lol. I have made plenty of mistakes this year, but have learned many things, so it has not been in vain. The squash has only had a few female flowers so far and they died before I caught them to pollinate. I have a few coming on now, but I don't even know if it's worth trying to polinate them this late. Better luck next year perhaps?

All I've been successful with has been the jalepeno and the tomatoes :( nothing else has done much this year. I guess I don't have enough pollinators near my balcony. I can't wait for this education I'm getting to really kick in. I'll be in the greenhouse a lot more come spring, so should be well prepared for next year!

I will chime in and confirm what others have stated on the options for control of both powdery mildews and spider mites.

IMO, neem is a good choice for both issues, but will be particularly effective against powdery mildew. I would up my application if you are treating once a week, given your balcony gets some of the rain that we have been getting every other day. Neem oil washes off quite quickly, so try treating slightly more frequent for a week or so, like every three days and see if you get some abatement.

Spider mites are hard, tough little creatures to deal with. If you can move the plants around to encourage more airflow between the plants, you may see some relief rather quickly. Streams of water are effective, particularly aimed at removing webbing, which can be necessary for egg laying. An alternative to the neem and physically knocking them off is a treatment of horticultural oil. Super cheap, easy to apply, non-toxic, and effective. Stay away from miticides and other chemicals as they rarely aide.

Good luck and keep at them!

Here is a link that might be useful: Spider mite fact sheet

What an honor... advice from the bugdoc! Thanks, by the way :) I will be checking out that horticulture oil for sure. Sounds like some good stuff.

I'm actually surprised my landscape teacher didn't mention it, but I'm sure he might have some around or at least know of it. Probably slipped his mind, as he also suggested a miticide.

I'm learning so much, but we've moved into irrigation now, so won;t be focusing as heavily on plants again until spring :(. We are, however, growing a nice batch of poinsettas for the fall sale, which is kind of exciting. Thanks again :D

I should mention treatment with hort oils should be done when the plants are not, and will not be, exposed to direct sunlight. The evening hours are a great time for treatment so the oils can settle in overnight. Direct sunlight may burn the leaf surfaces once oils are applied.

I hope one of the options helps. I'm not very good with vegetable issues, but I dabble a little in woody plant issues and am learning about perennials as much as I can. I teach at CSU in Fort Collins on urban and forest insects and diseases of woody plants. Most of the students are forestry students, but I do teach some hort students as well. Just out of curiosity, who is your teacher and where are you studying?

Good luck.

I'm at Pickens Tech... it's Bill Cary. He's pretty awesome, in my opinion :). This course is so hands on and not the "traditional" education I'd grown accustomed to. It's more so a landscape program, but I'm getting a couple certificates... one for greenhouse operations/management and one for landscape design. I LOVE it! My husband has also joined me in the program so we are taking it together. Gearing up for what will hopefully turn into our own business one day. Take care.

It's so refreshing to read that you found a great program. I've never met Bill Cary but sounds like you are in good hands. Congratulations!

I hope it turns into a great business adventure for you both.
Happy learning!