Tomato time!
Love of the tomato
Tomatoes are the iconic veggie garden plant, and probably the most versatile crop we can grow in zone 4b since tomato storage and preservation can be done in multiple ways. At the same time, tomatoes are one of the most fussy crops we grow. In order to get a worthwhile yield, not only is a truly sunny spot with good soil needed, but you also likely need to consider trellising, pruning, mulching, watering and scouting for diseases at some point during the growing season.
That being said, they are our highest productivity vegetable crop for home gardens in Minnesota at 4.5 pounds or 15.63 servings/ square foot! So they are worth the effort. See this publication for all the top yielding crops in Minnesota gardens. It is totally possible to grow your annual tomato supply in a Minnesota garden.
The little free seed distribution sites are now stocking tomato seeds. Find them sorted with the other Warm Season seeds for indoor starting. We are trying to offer a number of different varieties, and as with other crops, and are regularly restocking and updating the offerings in the cabinets. Check back frequently!
Tomato seed starting
Tomatoes are usually started indoors. You can use traditional indoor seed starting if you have supplies. No worries if you do not, instead try the indoor wicking container method. The wicking container method is a solid alternative that uses regular household supplies once you have seeds and potting soil. It is also possible to use the outdoor winter sowing method for tomatoes, a good option if you do not have indoor situation for seed starting. Winter sown seedlings will be a bit smaller than plants started indoors, but they will quickly catch-up. Regardless of which type of starting you choose, take extra care to label them well so you know which variety is which. Consider double labeling seed starting containers to prevent mystery tomatoes due to markers fading, peeling off tape, or sticks falling out. Labeling is important with tomatoes so you can identify the varieties you love for future seasons AND because they are so easy to save seeds from.
Tomato variety matters
Take a little time to learn about the tomato varieties you have by looking yours up on the web. There are literally tens of thousands of varieties! Tomato growing techniques and the potential to save seeds are dependent on the variety you have planted. Here are some characteristics you will want to know about the tomato plants you install into your garden:
The number of days until harvest. Some tomatoes have a very long growing season and your wait-time until picking takes until September-October. A rule of thumb is the larger the tomato, the longer time until harvest. Strive to mix up the varieties to your tomato patch so that at least 1 plant is harvestable earlier than the others. Really short season tomatoes might be 50-60 days, longest season tomatoes run 80-100 days; a big difference. Plant and seed descriptions will list the number of day until maturity or harvest. This usually means from when you transplant a seedling. Look up this information on the web for the seed names that you have.
Bush vs Vining tomatoes. Most tomato plants are vines and are usually categorized as “Indeterminate”. Tomato vines in good soil and sun can easily grow taller than 6 ft and really do best when trellised. Once the fruit matures, harvesting from indeterminate vining tomatoes happens daily until freezing temperatures in the Autumn. Do some estimation to see how many tall, trellised plants can actually fit your space & supplies.
Bush tomatoes, or “Determinate” types, are generally much shorter, can get by with less space, smaller trellises, and are particularly well suited for containers because they do not vine. Determinate tomatoes are favored by people who like to do food preserving because they can be harvested at one time.
Disease resistance. Some tomato varieties have disease resistance naturally, or bred into them, most do not. Tomato disease is almost a certainty in our climate, even after you take steps to prevent diseases. It often comes down to a late-season sprint between frost and the tomato disease to see who will win. To hedge your bets, it might be good to plant at least 1 variety that has disease resistance. You will find disease resistance coded by a series of letters following the variety name such as HR: F, IR: N or HR: F2, FOR, LM, TMV, TOMV, V. The different abbreviations code for different diseases. Unfortunately, varieties with these codes are not generally heirloom, heritage, open-pollinated or saved varieties that provide us with a well-loved array of colors, shapes and sizes of tomatoes we adore. To balance disease with diversity, hunt down 1 plant that has resistance to add insurance against your yield. Don’t let tomato disease potential turn you away from trying tomatoes, they are too valuable a crop! There are lots of ways you can slow disease progression.
Open pollenated versus Hybrid varieties- When choosing tomato varieties, it is important to know if the seed is a hybrid. Hybrids often have specific traits that we really desire (i.e. disease resistance), but those traits will not consistently be passed down to the next generation of seeds. Open pollenated varieties have stable traits that carryover from generation to generation. Why is this important? Saving tomato seeds is a easy gardening skill to try, and it allows you to have access to your favorite varieties year after year. Your seed saving plans begin when when you plant your garden; Open pollinated varieties allow for such plans. Seed Savers Exchange describes hybrids vs open pollinated more detailed here.
Growing tomatoes
There is lots of guides for growing tomatoes available. Be sure to use information that is tailored to northern gardening for the advice to be applicable to our short growing season. Increase your odds by rotating crops, trellising, mulching, keeping leaves dry and scouting for issues. Here are suggestions from from Idaho Extension which are comprehensive. Closer to home, the U of MN offers these tips.