Should You Keep Volunteer Tomatoes?

25 April 2014, written by Barbara Pleasant

No matter how long you grow a vegetable garden, you are never immune to the allure of proud little tomato seedlings that plant themselves in your compost pile, your flowerbed, or maybe the crevices in a stone walkway. One part of us wants to honour the gallantry of tomato seedlings that appear out of nowhere, but we are suspicious. What genes are they carrying? Was their mama a delicious variety you grew and loved, or the one you swore you'd never grow again?

The Case for Keeping Volunteer Tomatoes

The case for keeping a few volunteer tomato seedlings starts with the fact that it's free, fun, and feels like the right thing to do. After waiting so long for spring, pulling up the valiant little darlings and tossing them back into the compost feels a bit unbalanced, which tilts back to right when you give in and say "All right, I'll keep you and you" and start piling mulch around the base of the Chosen Ones.

Many gardeners who have done this have been amazed at the hardiness and vigour of tomatoes allowed to choose their own growing spaces, but there is no guarantee that the plant will bear a prolific crop of tasty fruits. However, if you know your garden's tomato-growing history, you may be able to make a good guess based on leaf types.

The majority of tomato varieties have what are called normal-shaped leaves, while those with broader, flatter, more pointed leaves have the "potato leaf" characteristic. Some cherry tomatoes have small, finely cut leaves that make them recognisable, too.

In my garden, I frequently grow two potato-leaf tomato varieties-- 'Stupice' and 'Brandywine' (which also comes in a normal-leaf version which I have never grown). So, when I see potato-leaf tomato seedlings popping up among the peas, I can reasonably believe that they are one of these varieties. Location can be a clue to the type of tomato seedling you have, too. Volunteer tomatoes that appear where paste tomatoes grew the year before are highly likely to be red plums. Cherry tomatoes are seedy to start with, so they are often well represented in a garden's crop of volunteer tomatoes. This is good only if you want or need more cherry tomatoes.

Will You Be Sorry?

Adopting volunteer tomato seedlings is choosing an adventure into the unknown, which is fine when you have a little space to spare and there are no other victims. When tomato volunteers grow in awkward places like the bean patch or the carrot bed, they must be taken out and the sooner, the better. Vigorous tomatoes can quickly become bullies that overtake smaller crops. A huge tomato plant can render your compost pile inaccessible, too. After weeks of welcome company, it can turn into an unwanted guest.

Then there is the much-touted risk of disease among self-sown tomato seedlings, but I have never heard a first-hand report of a volunteer tomato leading to a disease outbreak in a home garden. However, I often have seen evidence of early blight (dark spots on low leaves) on volunteer tomato seedlings that appear in spring – probably because they grow so close to cool ground, and get drenched daily with dew. For this reason, I pull and compost volunteer tomato seedlings that appear in April and May lest they become a nursery for early blight fungi. Spontaneous seedlings that appear in warmer June weather grow fast and clean, and these plants can make opportune replacements for expired spring crops.

Who stays and who goes? With volunteer tomato seedlings as with so many things, the best choices show a blending of head and heart.

By Barbara Pleasant