What is tomato blight and how do I prevent it?

Tomato blight is a fungal infection that can reduce the quality and number of tomatoes harvested from each plant. Its spores live in the soil. They can get splashed up on to the leaves while watering if the hose is turned on too far. You'll first notice the lower leaves with brown patches on them. That's when you need to take action so it doesn't affect your whole plant and spread to other plots. Many of our members grow tomatoes. That means it's important to be a good plot neighbor by staying on top of blight so that as few plants are affected as possible.

One way to prevent blight from infecting your tomatoes is to spread a layer of hay around the base of each plant. Salt marsh hay is the best. It is sold in bales at garden centers like Ricky's in Union Square and Mahoney's (various locations) for about $20. One bale will probably be enough for 4-5 gardeners to share. (Try not to let the hay get wet before you spread it around your plants.) The surface layer of hay prevents soil from getting splashed onto lower leaves. That's it! Simple, yet very effective.

Side note: If you can't get salt marsh hay, try to make sure whatever hay you use has not been treated with chemicals. Sometimes, decorative hay available at craft supply stores has been treated. That would not be good to use on plants you plan to consume, like tomatoes.

Another way to keep fungi from thriving is to water in the morning, rather than in the late afternoon or evening. By watering early, there's time for the plant to dry off before nightfall, when fungi thrives. Try to water the dirt, not the leaves.

If you still notice brown patches on lower leaves, cut the branch off as close to the stem as possible and throw them away at home. Do NOT compost them or till them back in to your plot soil, because you are then spreading the blight spores further.

Hopefully, these tips will help avoid trouble for your tomatoes. Do you have other ideas for how to control blight? Leave a comment on the post on our Facebook page:

https://www.facebook.com/GardensforCharlestown

These simple precautions should prevent most plants from getting ruined by blight. Happy gardening!