Tomato blight can be tricky to eliminate

Q: I had either early blight or late blight on our tomatoes last summer. We mulch our whole garden with newspaper and paper grocery bags, then cover that with grass clipping or shredded leaves.

We trim the tomato plants up 18 inches from the mulch, hopefully to avoid blight. We rotate tomato plants every year in our 70-by-25-foot garden. Maybe I should eliminate tomatoes from our garden entirely? I don't know what I can do.

Answer: You are doing all the right things to prevent disease problems like early and late blight. Try thinning the plants by removing some of the suckers to increase air flow and light penetration while decreasing the risk of disease.

Be sure to remove and destroy, burn or bury all infected plants and fruit as soon as it is discovered and definitely at the end of the season.

You can also try growing early- and late-blight-resistant tomato varieties this year. Iron Lady, Defiant, Mountain Magic and Aunt Ginny’s Purple have shown resistance to both diseases.

Mountain Supreme, Jasper, Juliet and Verona are resistant to early blight. Late-blight-resistant tomatoes include Cherry Bomb, Jasper, Lemon Drop, Mountain Merit, Mr Stripey, Prudence Purple and Stellar. Check tags and catalogs for other resistant varieties.

Keep in mind that resistance doesn’t mean the plants won’t ever get the disease. It just means they are less likely to be infected.

Because this appears to be a chronic problem, you may choose to skip growing tomatoes for a year or two or try using a copper-containing organic fungicide as a preventative. Be sure to read and follow all label directions carefully.

Q: I'd like to plant a cover crop for the summer in my unused garden space & a cover crop for the winter. Will I have to worry about unwanted seeds once the crops are plowed under? Any help is welcome.

A: Cover crops are typically annual plants. Terminating them before they flower maximizes the benefits they provide, makes cutting and incorporating easier and avoids the problem with unwanted seedling.

Some gardeners cut the cover crop short with a scythe or mower and leave the debris lay. It acts as a mulch and slowly breaks down to further improve the soil. Others incorporate the cover crop either when cutting or after cutting. This speeds the decomposition of the cover crop. The University of Wisconsin Extension Service’s “Using Cover Crops and Green Manures in the Home Garden”  and Washington State University Extension Fact Sheet FS119E provide detailed information on using cover crops.

Email questions to Melinda Myers through melindamyers.com, or write her at P.O. Box 798, Mukwonago, WI 53149.