One of my favorite things to plant, grow, and eat every year is tomatoes. Here is one thing that I have learned about buying tomatoes. First of all, some things are better to buy and plant as seeds, others as plants. Tomatoes - to me - belong in the latter category. My first year gardening I bought eight plants and planted them all. One died leaving me with seven. We also had a problem with black spots on the leaves, vermacillan wilt, and blossom end rot. One thing that will help with all of these things is to:
A.) Buy a variety of tomato that is vermacillian resistant. (may not be spelled correctly)
B.) Fertilize once a month - but not too much. If you do experience fertilizer burn, just water the plant almost to death. It should recover.
C.) Don't over-water
D.) If you or someone you know has a fish tank - use the water from the tank when they clean it out at the end of every month - GREAT fertilizer.
E.) Finally, and most importantly, pinch off any suckers. The best thing about this is that you can buy a plant that has a few suckers on it (or wait, they will come). lrt it grow a couple if inches, and replant just the sucker (put 80% of the little sucker in the ground and watch and wait!). It will grow and be just as healthy and productive as the original plant.
Suckers are the part of the tomato plant that stems from between two essential parts of the vine. I wish I had a picture to show you; but I didn't know I would be posting this today, so I didn't take a picture last year. (I will this year to show you later, or maybe I can find one on the web and post it.) In an effort to make sure you understand what a sucker is...you have the main vine, then you will have off shoots from that vine. After a few days you will see little vines beginning to grow out of the "v". That is a sucker. It will suck nutrients from your plant and will cause it to grow more vines and leaves than tomatoes. Also, your tomatoes will be better quality if you are faithful to pinch suckers off. Anything that does not come off the main vine can probably be cut or pinched off. Last year I even cut off some extra leaves. Cutting off extra will ensure that oxygen,bees,butterflies, and light can easily get to your blossoms and eventually fruit. If you don't know what you are doing, don't cut anything. It will still grow and you will be fine. If you plant more than one bush; pinch and cut what you think is un-important and see if everything is ok before you try it on the others.
Hope this bit of advice is a help to all tomato lovers.