All of us from time to time loose a plant or two to weather, improper care, accident, etc. Coleus, however, are not finicky plants. They are only "tender" in respect to temperatures.. They do not need to be fussed over, and unlike many plants will tolerate all the fussing we addicts care to give.

Why then, when I have grown coleus for years, and mastered the dos and don'ts of their culture and have provide this years collection with the same soil, light, protection, routine as in previous years are anumber of my coleus failing to thrive?

First , I grow all of my coleus in containers and rarely combine them with other plants in the same pot. None of mine are wintered over, they are all fresh this season , purchashed in 4" or large pots from the same six local vendors as the last 3 years. I collect the plants, take cuttings to multiply, pot up , pinch, and end the season with about 40 large containers of gorgeous coleus.

This year I collected, took cuttings and potted up, but within 2 weeks I began to notice that some of the mother plants and some of the plants I had left full and planted in their large containers were "not happy" I collected more, and indeed some of these were also unhappy. Why? I counted it up to fickle weather and knew that once weather settled down so would my plants.

The usual was not to be and these unhappy plants did not begin to thrive, in fact they went down hill with leaf drop, brown patches on leaves , leaf curl and distortion, especially in the sparse new growth. No evidence of mealies or other insect infestation. What was going on? Was my less than green thumb asserting itself once again?

I separated these plants, and in so doing began to realize that they were the same varieties and primarily from three vendors. I began to research what might be going on.

To my sadness and dismay, I found references to two newly discovered diseases in coleus, one, a virus and the second, a downy mildew the symptoms of which I was seeing in my plants! Further, both diseases are highly contagious and could spread to my entire collection.

Last Sat I returned nine plants to one of my favorite garden centers and asked for a refund after explaining that the plants they had sold me were diseased. At first they refused because "Coleus are only annuals", then they offered an exchange which I refused be-cause it was quite likely that their other coleus were also infected. And I did show them several symptoms on their current stock. They pulled some varieties and said they would be contacting their supplier on Mon.. I got my refund.

Now I am left to wonder whether coleus will have the same sort of saga that has plagued Hostas and whether I can count on a healthy supply of coleus to feed my addiction. I have a new responce to why bad things happen to good coleus mammas and poppas.

Judy

Judy, thanks for the heads-up.
Chris Baker, a great coleus hybridizer in Ohio has taught that Thirps are the main disease carrier for coleus. He puts his "stock" plants in hot boxes with controlled heat for 2(?) weeks to kill disease
Here are the things I might try to fix them if I found these in my collection.
Try a half strength Mixture of Bayer's complete Rose and flower food. It has 3 systematic treatments Insects,virus and fertilizer.
It says not for potted plants, but I am not deterred. I often set them in a tray of 1/2 mix and let them soak up what they want.
So glad we have a new Coleus buddy.
Sorry this is spotty, but I'm in a dash.

Thanks for your response Sydney.

Yes, it is a heads up , which is why I returned those plants...so that growers and suppliers of these now popular plants need to get their cultural act togetherand nip these problems in the bud . There is no excuse for shipping out less than healthy plants. Although the big box stores sold countless tomatoe starts last season even though it was known they were infected, and one can still find Hostas with clear signs of disease for sale almost everywhere, it isn't right

Yes, I as a consumer can be careful, and try to treat my own plants as you have suggested above, but the problem starts long before I get my coleus fix for the season.

And here's something else: two of the plants I returned were Fishnet Stockings and Sedona, varietiies coleus lovers are attracted to but have widely divergent success with. Could it be that these two varieties are so tainted that they will not consistently grow well for the majority of us?

What other varieties will we loose to a careless industry whose bottom line is profit, not plants and people? Where and who are the growers with integrity like Chris of Bakers Acres? Or Pam at Rosy Dawn?

I have to stop for now and research the 13 new plants I just got today from Rosy Dawn I ordered late last Sat , putting my refunded money to a more justified use!

Judy

Thanks for the information. This was all very interesting.

Patty

I don't know how to create links here but just googling "coleus disease" yields the first reference I read entitled "New Disease in Coleus". Also, google images for coleus disease, or coleus virus, or coleus downy mildew are helpful references.

So I'm changing my buying stategies from buy only good looking coleus to buy only good looking coleus where all other coleus on premises continue to exhibit health for at least two weeks, and then quarantine any new stock brought home.

My days as a coleus rescuer have ended (sad face)

My Rosy Dawn order is beautiful and quarentined in their new pots with new soil for their own protection!

Judy

Here are some pics of coleus with suspected downy Mildew.

Note curled leaves and black streaks

More

And

Another

Again

Or

Yet another

Seems that infected plants, those exposed to mildew spores from other plants or infected growing environment or handling appear ok until conditions are right. Those conditions are warm/moist, cool/moist, crowding and poor air circulation among others.

Since these are conditions typically found in greenhose production and effective treatment/eradication is still being researched , I am trying to follow the protocol of

1) Not purchasing any coleus that has any leaf problem whatsoever, including leaf drop
2) Not purchasing a coleus plant that looks healthy if displayed with others that do not
3) Isolating and monitoring any new coleus for at least two weeks before intro to garden
4) Immediately pulling and destroying any coleus the begings to exhibit symptoms, not trying to "save" it.
5) Not overcrowding my plantings
6) Watering the soil and not the leaves when possible
7) Being scrupulous about cleanup as I can spread the spores unwittinly

Your thoughts/comments?

Judy