You have a "zinnia disease"..I think it's a fungus and leaving the last year's plants in the ground spreads it.
It's too late this year, but next year, if you still want to grow zinnias, you need to spray them with a fungicide, I have used benomyl and phalthan, and be vigilant. If yous ee one crispy or strange leaf, pick it off and dispose of it.
Linda C

Linda,

Can my Zinnias still be diseased even if I did not leave last years plants in? Also, I don't even have them in the same spot this year and amended my soil where they are really well. Right now, I have Zinnias about a foot tall with no lower leaves, just a beautiful bud forming as I couldn't handle looking at the leaves anymore.

Zinnias are also prone to mildew. They need good air circulation and water the ground, not from above. Even if you took out the plants from last summer, new ones can still get diseased.

Kat

Kaky,

The pretty pictures of zinnias aren't a scam. You can scroll down in this National Garden Bureau zinnia fact sheet to read basic information about zinnias.

The Zany for Zinnias journal also has a lot of zinnia information. You need to scroll down there to see all of the information.

The Butterfly Gardening site has some good information from the Missouri Botanical Garden on What's the Best Way to Grow Zinnias?.

MM

Yep....Kat said it....but it's a sure thing if you have diseased plants and don't remove them from the bed before replanting.
And when you do water....be sure that the soil doesn't splash onto the leaves.....a good reason to mulch.
Linda C

Thank you for all of the info. I'll check the links and also look into zinnia disease. ... I have heard about the mildew issue (actually, that's the only advice I'd been getting and couldn't imagine it was the whole story). ... I do have fresh mulch in the bed.

Thanks again.

Thanks as well for all the info. Maine Man was a big help and the info from Kat and Linda about watering is a great help as I have not been cautious and do soak the leaves pretty good when I do water. I do not have mulch and one of my Zinnia patches does get alot of soil splashed up on them after rain or watering. Thanks again to all.

i wouldnt waste time.. money.. and risk health.. to use chemicals on zinnia ...

though stunning .... they arent worth the hassle ... gave up on them years ago ...

but.. if you must continue with them .... consider using them as a short season crop .... removing them when they are starting to get the UGH's ... and plant a second crop of fall flowering plants .... or have them already there in spring ...

up here in the great white north.. kales are used for late summer/fall color .... but i bet you are not in cabbage country ....

NO ONE EVER SAID YOU HAVE TO LEAVE THEM THERE ALL YEAR.. enjoy them, then move on ...

ken

Ken,

Good advice. Maybe I will just get a couple of nice bouquets out of them and pull em out. Kale does great here in Maine. Maybe I will use them with my Mums where my Zinnias are. Thanks.

Cosmolover

Ken,

"I wouldn't waste time.. money.. and risk health.. to use chemicals on zinnia ..."

There are plenty of safe "chemicals" that you can use on zinnias. One is a product called GreenCure®, whose active ingredient is potassium bicarbonate, which is an ingredient in baking powder. I don't have disease problems in my zinnias during the Spring and Summer, but I do spray regularly with GreenCure in the Fall, and it works very well for me. It is effective against a long list of foliage diseases.

"though stunning .... they aren't worth the hassle ... gave up on them years ago ... "

Zinnias are one of the easiest flowers to grow, and are frequently recommended as a good "starter" flower for children.

MM

While not disagreeing with the above posters, I'm with rhizo. Buying disease resistant varieties is one of the best reasons I know for spending money on seed. I highly recommend the Profusion and Crystal Series of zinnias. I have grown them for years, and they never fail to look great. No, they are not cut flower size, but they sure do add alot to beds and borders. Oh, and this year, I am growing Zinnia Highlights and they are truly gorgeous. The prettiest clear yellow you ever saw. I wish I knew how to post pictures, I'd show you my bed of them with Mystic Spires blue salvia behind them.

Yes, I've read about the profusion series and look forward to growing them. Meant to this year, but just ran out of time. I didn't see seeds offered for sale in the big box stores and need to make sure and get some from Park, or someplace similar. ... But, yes, I grow the traditional zinnias specifically to cut... Of course, when they're ugly as sin, that's not going to happen anyway. Thanks again for all!

integrated pest management suggest crop rotation over spraying ANYTHING ...

all i wanted to point out was that you dont need to do anything.. if you consider crop rotation ... or plan such ....

when its ugly .. its dead.. in my garden .... having served its purpose ...

and if you planted/planned other things ... no problem ..

and no additional cost of sprays ... as rhizo noted... if you make the right decision on which to plant.. again.. you never need to spray ....

i mean really .. and i know you are all die hard Z lovers.. dont get me wrong ... and knock yourselves out on your passion ....

but a plant you need to spray is not as EASY and CAREFREE as you suggest ...

God Bless the Z lovers .... no insult intended .... just think outside the box ... when your inclination is to start spraying ...

ken

Besides the Profusion and Crystal series of zinnia (I LOVE them), I've also had pretty good luck with Magellan. Donna, tell me more about 'Highlights'! Is it a series or a color selection in a series? I can't find anything on it.

I read about Zinnia Highlight last fall in Horticulture Magazine. I love yellow, and am always on the lookout for something that will go all summer long. Anyway, Burpee carries it, and I got the impression (maybe that's the impression they wanted to project) that only Burpee has it. Anyway, as best I can tell, this seed should be part of the Profusion series. Its habit, bloom style, everything, is identical to the Profusions. But, the color is a perfectly clear, cool, bright yellow. The center is golden orange (like all profusions), but otherwise there is no gold or orange in the yellow. I will definitely get more of it next year.

Zinnias can be either the easiest plant on earth, or snot up right now. They are hot weather plants, and very prone to really getting nasty if under or overwatered. Much of the ugliness is strictly cultural and a clip job to let them rejuvenate is all you need to do. Some of it can be disease brought on by weather conditions. It's the kind of leaf spot not going to dwell in your garden soil or kill everything.

I use a lot of profusions, and there is also one my seed broker suggested for next year after going to some of the trials and this one is called Zahara. Much like a profusion, like Donna says, only with a better range of colours.

I've just looked at those pretty Zaharas, very nice! I think I'll have to try some. And maybe Highlights, too.

I planted a zinnia garden a couple years ago and came across a hint to sprinkle cinnamon on your plants to keep the disease at bay so I did when they started to get not so nice looking and it helped. The plants turned out beautifully! I have about 30 zinnia plants and will do the same for them this year.

I'm going out to buy some extra cinnamon this morning!!Thanks!!

Has anyone here tried carefully spraying a very dilute bleach/water solution in the dormant season on the soil as a way to deal with fungus? In theory wouldn't bleach kill the fungus?

I haven't tried it because I'm afraid it would kill dormant perennials, but I may try it on just a scrap of the area where fungus seems to thrive.

I'm going to also post this in the appropriate forum, but was just curious to see if any of you zinna folks had tried it.

FiveMurfs,

I haven't tried the bleach in the garden. I do use it in the rinse water to sterilize pots that I have washed. I would be very hesitant to spray the soil with bleach to kill fungi because I think it might also kill beneficial soil microbes and earthworms and such. Good garden loam is a living, breathing entity and I wouldn't want to kill it. And I say that, while insisting that I am not an organic gardener.

MM

Thanks, MM, for your response. I guess I didn't think it through to the logical conclusion, that bleach would kill everything. I'm not organic either, but I do appreciate that the soil and all it contains benefit the plants.

Ha! You know, MM and 5M, that you sound like organic gardeners 'in training', lol! Truthfully and factually, the more you foster the soil, the less you will ever have to rely on chemicals for anything.

You are right, MM, about the bleach doing damage to the soil microorganisms and the environment they create for healthy plants. By all means, practice basic housekeeping practices in the garden, but don't try to disinfect the soil.

I know I am late posting with this, but wanted to give you another option.

You can treat the area where you want to plant the zinnias without using any chemicals. Just put clear plastic over the area (black plastic won't work) and leave it there over the winter. Hold it in place with rocks or bricks. It also eliminates most weeds. This is called solarizing. The combination of the plastic and the sun will "cook" the fungus causing your problem.

When you are ready to plant next year, remove the plastic and plant as usual.

Kay

Thanks Kay. Any input is greatly appreciated. My Zinnias are finally blooming and are gorgeous even though I have stripped off any leaves they have. I don't want to give up on them as I love the way they look in a vase on my dining room table (even without the leaves). I will try the plastic this fall.

Can anyone tell me what makes the leaves on the Zinnia turn yellow. Of course, I do have some of the black spot problem but, I seem to have that in control right now. I had read an article last year if one starts early in the spring and sprays with Sevin/water that it will help control all the pest, mildew, spots, etc. So, at the very first of humid weather I started spraying about 2 or 3 times a week and it has helped to keep the foliage looking green and beautiful.

I've always sprinkled cinnamon on and around my zinnias. This supposedly keeps them healthy and disease resistant. It has worked for me as my zinnias have always looked very healthy. No comment on the rest of the garden though.

stylintn,

"Can anyone tell me what makes the leaves on the Zinnia turn yellow?"

Zinnias need at least 6 hours of full sunlight per day, but it could be a deficiency of one or more nutrients, such as nitrogen, iron, magnesium, etc. My advice to spray them with a foliar feeding of a good complete nutrient formula. I like Miracle Gro Tomato Food for my outdoor zinnias, because it contains extra magnesium, which is a component of chlorophyll. Of course, I dilute the Miracle Gro with water, about one tablespoon per gallon. Spray on plenty, allowing some to drip off for feeding the roots as well. Spray on whatever time of day is convenient for you.

ZM
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