Spring Slow Growth of Tomato

Q. I planted Roma, Better Boy and Early Girl tomato varieties this spring. Over 45 days later they've not gotten much bigger than when I brought them home from the nursery. 

A. Be careful when mixing woodchips or other woody soil amendments in the soil. These woodchips require a lot of extra nitrogen as they decompose, a.k.a., rot. They will slow growth and cause yellowing if mixed in the soil without any follow-up nitrogen fertilizer applications. It is very important to add extra nitrogen fertilizer to the soil if you decide to mix anything in the soil made from wood products.

            The weather has been colder and wetter than normal. This has also slowed down the growth of warm season vegetables like tomatoes, peppers, eggplant and the like. Be patient.

Wall o water has been around for a long time and it works a little better than hot caps but more expensive. Be sure to warm the soil before putting transplants out in wall of water or cold soils will slow them down.

            Hot caps aren’t used much anymore but those along with Wall-o-water plant sleeves were made to speed up the growth of plants during cool weather. Rediscover these nifty little garden additions. They keep plants warmer and speed the growth of warm season vegetables when weather is cool.

            On the remote chance something else might be going on, inspect some roots of these plants and see if there are any small “balls” growing on them. 

Root knot nematode on tomato

If found this might indicate nematodes are in the soil and a problem. Nematodes infesting plant roots can slow them down as well. Not much you can do if they are present except replace the soil and plants. This is one reason container gardening can be worthwhile. The containers can be sanitized and the soil replaced more easily than in a garden bed.