tomatoes and curly top virus « giantveggiegardener

I have written about this problem a few times on this site and it might be worth a visit to one of my previous posts if you are interested in learning about CTV:

Identifiying Tomato Curley Top Virus

In addition there is more info on this problem through New Mexico State University (NMSU) here.

The reason I put row cover over my plants is to have a physical protection to keep the Beet Leafhopper off of them. I remove the row covers when the monsoons come in July as they seem to either leave or become suppressed and then I usually don’t have any problems with leafhoppers and CTV. No insecticides seem to work. If it seems that I harp on this problem, I do! I just want you all to be successful with tomato growing here.

Photo credits:
curly top disease – photo courtesy of http://ucanr.org/blogs/blogcore/postdetail.cfm?postnum=3352

Curly Top Tomato Virus
Last year, the Beet Leafhopper which transmits ‘Curly Top Tomato Virus’ was rampant in our gardens and devastated many tomato plants. I lost 50% of my tomato plants. The Beet Leafhopper flies in on the winds in early June through July, jump on the tomato plants and taste them. They don’t even like to eat tomato plants but sample them, transmitting the disease in the process.

beet leafhopper – courtesy of http://www.coopext.colostate.edu/TRA/PLANTS/curlytopvirus.shtml

Identifying Beet Leafhoppers
You will know if they are here as they come in waves and when you walk around your garden, you’ll see a lot of jumping little green bugs that fly off when you walk by. Then they leave—flying to the next garden. Because of this, you can’t really spray anything to get them—here today, gone tomorrow. By the time you notice something is wrong with your plant, they are long gone. It takes about 2 weeks for symptoms to show up.

Symptoms
Your tomato plant leaves will start to curl and the underside of the leaves will turn a purplish color The leaves then start to wilt and the plant will look stunted. You might think it needs water but it doesn’t, it is sick and won’t recover. ‘Curly-Top’ is only transmitted from bug to plant is NOT transmitted from plant to plant hence you will see a healthy plant next to a sick plant.

Remedies
There is NO CURE for this virus and if your tomato (or pepper for that matter) shows signs of the disease, you should pull the plant. You could leave the plant in BUT if another wave of leafhoppers come by and a healthy leafhopper bites your sick plant, it only takes 10 minutes in 90°F weather for it to be able to transmit the disease to one of your healthy plants. The best thing to do is pull any sick plant and dispose of it.

Leafhoppers do not like shade and if your plants are partially shaded, that may help keep them off but since most of us grow tomatoes in full sun that might be difficult.

Create a physical barrier with row cover

Row cover over the tomato plants in my garden

Another thing you can do is create a physical barrier between the bugs and your plants. This year, I’m covering my tomato plants with row cover until the bugs pass. Wrap the row cover around your tomato cage and put a piece on top of the cage BEFORE they come.

Lastly you could put out some tomatoes later in the season after the bugs leave. Last year when I was out at the Santa Fe Community Garden I noticed many rows of sick tomato plants but one row of perfectly healthy plants and when I asked about them, it turned out they were put out about a month later than the rest of them and by then the leafhoppers were gone.

Dry, sunny, windy weather are perfect conditions for the leafhoppers so look out this summer-conditions are ripe again!