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Aug 17, 2017 6:43 AM CST
My zinnias, cockscombs, and other plants have had something on them that turns the leaves brown and they wither and fall off. This started early in the season and has continued. I do compost and now am wondering if my soil is out of balance. I have a friend who mostly has his garden in plain soil without much added compost or peat moss or garden soil or potting soil he could buy. His plants seem to be free of fungus or anything that might plague a plant. In my compost I put tea and coffee grounds, peelings from vegetables and fruits, newspaper and that's about it. I don't put grass clippings because of the weeds in them. I live in a condo and there are lots of weeds in the grass. What is a good balanced soil? What are some soil suggestions for just a small flower and tomato garden? This is the worst year I have ever had with flowers. White flies are also a big problem. I don't like to use pesticides, and so have only used a couple of products a couple of times that are supposedly environmentally safe. I cut a plant completely back because it was looking so bad and it had new growth and looked good and then the leaves started getting a whitish color running through them. Is that an indication of white flies? How in the world does one get rid of them? Thanks for any help you can give.
Name: Cindy
Hobart, IN zone 5
aka CindyMzone5
Celebrating Gardening: 2015 Plant Identifier
Aug 17, 2017 6:54 AM CST
White flies can do a number on plants. Never had them until this year and they're a pain to get rid of. Don't know how they came to my garden - guessing potting soil. I'm not as relentless as I should be in spraying to get rid of them. Using Azamax but not as often as I should.
Only when the last tree has died and the last river has been poisoned and the last fish has been caught will we realize that we can't eat money. Cree proverb
Name: Rick R.
Minneapolis, MN, USA zone 4
I was one of the first 300 contributors to the plant database! Garden Sages The WITWIT Badge Garden Photography Region: Minnesota Hybridizer
Seed Starter Plant Identifier Million Pollinator Garden Challenge
Aug 17, 2017 8:17 AM CST
Most insects, including white fly, have their favorite plants to infest. If your neighbor does not grow the same plants as you do, a comparison that he does not have insects and you do, may or may not be valid. But if your plants grow more lushly than his, due to your better soil components and/or fertilizing, this would be more attractive to insects and disease. Slower developing, but still healthy growth that is less tender is less attractive to insects and disease. Watering practices may also play a role.

Most garden plants would be happy growing in pure compost. Your results certainly are not because you have used too much. Good compost is a soil stabilizer that buffers pH, soil fertility, porosity and improves soil health in general. The components of good compost can be myriads of things, your fruits and vegetables should add enough nitrogen that grass clippings would not be necessary. I am not a coffee drinker, but know how some people use it, I am guessing it composes a large portion of the compost. Ditto with newspaper. This is probably fine, but you may want to read up on the subject to ensure you're not making dire mistakes with your composting project. Search for "composting coffee grounds," "compost" or "newspaper compost" on this site or on google. As always, be checking the source of the information. You can't believe everything on the internet.
Southeast OK (Zone 7b)
Aug 17, 2017 8:18 AM CST
It would really help to have a picture of the plant/s that are affected. At one point I'm sitting here thinking rust for the leaves withering and dying. And then I'm thinking powdery mildew. Both will affect the zinnias. Zinnias need drought. They perform best in full sun with water maybe once a week to 10 days. If they live in moist conditions, they will get a bacterial disease (rust) and the leaves will become spotty with brown spots that eventually leave holes and kill the entire leaf (the wilting and dying off). It will start at the bottom of the plant and travel up. If it is a bacterial disease causing this, it can spread to other plants (celosia). I can't help with the powdery mildew as I never have that problem with my zins or any other plant. I do get the bacterial disease if I plant them close to my house where the dirt tends to stay cooler and wetter over the gardens that get full sun (meaning all day long, not just 6 hours). If we have a year with alot of rain (like this year), no matter what I do, I'll have the bacterial disease. It's why I plant other things in front of my zins. No sense in yanking them this late in the year and the shorter plants in front hide the bacterial disease. There's not much to combat that other than a fungicide and it's really not even worth it at this point. Post us a picture if you can and then we can get to dissecting the real problem and pointing you in the right direction.
Name: Anna Z.
Monroe, WI
Charter ATP Member Greenhouse Cat Lover Raises cows Region: Wisconsin
Aug 17, 2017 8:30 AM CST
The whiteflies are HORRIBLE on my 3 lantana plants...........doesn't make any difference on the season.

I mix compost in when I mix my potting medium.
Name: Yardenman
Maryland (Zone 7a)
Aug 17, 2017 10:29 AM CST
If it helps, I use a mix of 1/2 sifted peat moss, 1/3 sifted compost and the rest perlite and vermiculite. Good for seed starting. For planters, I add some 2-6-6 slow release organic fertilizer and some kelp meal for micro-nutrients.

My deck pots seem happy.

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[Last edited by Yardenman - Aug 17, 2017 10:30 AM (+)]
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Aug 18, 2017 10:37 AM CST
Thanks for all the comments about compost, zinnias, etc. It was very helpful. The supposed rust has been embarrassing this year as I transplanted some of my cockscombs, which looked so healthy when they were small, in the flower garden at my church. I also gave some to a neighbor who admired mine last year when they looked fabulous. Both at church and at my neighbors, they developed what I guess is rust. Is rust in the soil and what should I do to prevent it next year? I have never had it on the cockscombs before this year. The blooms on my cockscombs and zinnias are really pretty, but the leaves look so bad that I took them off my zinnias. Couldn't stand to look at them. I have just pulled the cockscombs up also as the leaves were so unsightly. Also, the comment about rich soil attracting pests was interesting as that could well be some of my problem with all of my compost and other additions as peat and top and potting soil. Has anyone used detergent in warm water to spray for white flies? I might try that but I remember using baking soda in water to spray my zinnias for mildew and I didn't like the results which didn't seem to work. I was interested in the one comment about never having mildew on her zinnias. What is your secret? I always have mildew later in the summer on them, but this year, the "rust" is new to me. I have a condo so it's hard to find a place where my zinnias would get more than 6 hours of sun. I planted some in pots on the patio so I could move them around to find the sun. The flowers are beautiful, but still rust? and now mildew is starting. Guess next year I will get a couple of large planters on rollers and try to find the sun outside somewhere for a longer period of time each day. I am wondering what they one gardener meant by sifted peat moss and sifted compost. Do you use a screen and what do you sift out of the soil? Is it beneficial as far as pests and diseases?
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