I am trying to grow tomato plants purchased a Home Depot but for the last 2 years I have had problems. I am planting using 5 gallon containers and use planting soil. The plants do well for about 1 month. Then, the leaves develop small black spots which eventually turn the leaves yellow then brown and wither and fall off. I have used Sevin dust frequently and fertilize often. The watering is done twice weekly by the lawn sprinklers and I do it with a sprinkler can again once a week. I used to plant the plants into the ground and had great results. 5 foot tall plants! Any suggestions would be greatly appreciated.
It sounds very like your plants are suffering from blight, I am sure though that someone will come along and tell you for sure. I was told a little earlier in the year it is best to grow your plants from seed and you can get blight resistant varieties I will try and find the post and put a link to it for you as I was told the varieties.
http://www.gardenstew.com/viewtopic.php ... highlight= this is the link to my post on blight problems and the repplies that I recieved
Could be blight or a fungus. My plants got that this summer later in the growing season. the fungus happens when your have decomposing material close by and it is very damp. Blight happens when water splashes back onto the plant when it rains etc. I grow my plants in tires now, the water doesn't splash up anymore. when the plants are little try to prevent over watering if you can. Work on the drainage. Did you put rocks in the potting mix in the pots? Rocks will help with the drainage so that top of the soil isn't too wet. Mix in compost and peat moss to also improve drainage.
Watering: move the containers out of sprinklers reach to avoid leaves getting wet: that causes prime conditions for the fungal disease(s) attacking them (early blight or septoria leaf spot). Soil: if it's "heavy" and retaining a lot of water, add perlite to "lighten" and allow better drainage: perlite aerates the soil while keeping it "cool", does NOT hold water. Bottom drainage: rocks work very well but are heavy. Try about 3 inches of styrofoam packaging "popcorn" in bottoms of containers, works like a charm! Allows excess water to easily drain, eliminates tomatoes getting "soggy feet". Tomato choices: there are some especially bred for the hot, humid Southeast conditions: seeds are available thru Tomato Growers Supply Co. of Fort Meyers, are listed in their catalogue. Otherwise look for hybridized varieties that have been bred to be repellant to various diseases. Will be a series of letters right after the tomatoes name, such as V,F,N,T and/or A. Transplanting: it really helps to work a GOOD handful of Epson Salts into bottom of hole before setting tomatoes in. Epsom Salts contain magnesium and sulfur, the latter of which aids in disease control. Another "trick" is planting a few onion bulblets and/or garlic cloves in those 5 gallon containers along with the tomatoes. The alliums release chemicals into the soil to fight diseases, also act as bug deterrants, are very good companion plants! Wishing you the best of growing, hope I've been of some help.
