Growing Tomatoes in Pots
Words and Photos by Jac Kyles Baker
Why I Grew Tomatoes
Ever tasted a warm, vine ripened tomato in the height of summer? A tomato just picked in the garden five minutes ago? Compare that to the insipid, hard tomatoes sitting in the typical air conditioned supermarket produce section.
The quality and variety of supermarket tomatoes is unimpressive. I scoffed at tomato prices in organic grocery stores. I refused to wake up early on Saturday mornings to journey to a farmer’s market. All good reasons to grow tomatoes myself.
The glossy pictures in gardening magazines and seed catalogs inflame the tomato lust. Descriptions promise: Delicious! Productive! Easy! I wanted all the colors, sizes and flavors. Visions of tomatoes for sandwiches, burgers, salads, tarts, pasta and pizza dance in my head.
Well. My small garden clashed with my tomato fantasy (or fever dream). Within that space, tomatoes needed adequate light. A house with narrow side yards only has so much light. And other plants I couldn’t live without needed some of that light. But I wouldn’t be denied my homegrown tomatoes.
The first summer I grew tomatoes in brick beds on the south facing side of the house. Despite my ignorance, most of the plants grew well. Was I able to put up shelves filled with brightly colored jars of tomatoes? No.
But I wasn’t a doomsday prepper. And my household's small. Opening the kitchen door and picking fresh tomatoes for meals was gratifying.
The Tomato Cultivars I Grew
Over the years, I tested more or less ten tomato varieties. All open pollinated. Most were unsuccessful. Some were suitable for warmer climates with longer seasons. Some needed more growing space. Some weren’t productive enough to grow again.
The reliable tomatoes came down to indeterminate* varieties Illini Star, Red Pear, Yellow Pear, Tigerella and Green Zebra. (See the bottom of the page for my fave tomato seed sources).
Two or three plants of the five cultivars satisfied my culinary needs. Yes, the ambitious gardener in me wanted a rainbow of tomato colors: black, orange, ivory, purple and pink tomatoes. Growing tomatoes that were expensive or difficult to find was the goal. Mission accomplished.
I'd never expect trendy tomato 'Green Zebra' to be reliable. Yet it was every year.
Tomato 'Yellow Pear' is so cute, flavorful and productive.
Tomato 'Tigerella' grew well in the brick planters when neighbors' trees created a microclimate. Not so much after trees were cut down. Too bad. They made flavorful tarts.
Tomato 'Red Pear' came before 'Yellow Pear.' Why two pears and not a cherry or grape tomato? I've never seen pear tomatoes in stores.
How I Grew Organic Tomatoes
I first grew tomatoes in brick planters on the south side of the house. My neighbors' photinia hedge and other trees created a protective microclimate. Otherwise, the intense sunlight would bake soil and plants.
An overzealous chainsaw wielder felled the photinia hedge. Other trees and shrubs shared the same fate. The microclimate vanished. “Uncomfortably hot” from 11 am to 6 pm was the new summer microclimate.
No amount of water or compost compensated for the bricks’ retained heat. The dry heat multiplied the spider mites. Tomatoes like heat. Right? Not so much. Production declined. What to do? (Turns out the brick planters’ intense heat suited peppers, eggplant, okra, black eyed peas. marigolds and zinnias).
Growing Tomatoes in Pots
I tried growing a privacy screen of potted trees. That failed. So I repurposed the pots for growing vegetables, flowers and herbs—mini cottage gardens in pots.
It worked. The large pots retained soil moisture. Plants received plenty of sunshine.
I dabbled with companion planting in the brick planters. I repeated that idea in three large pots. Scallions and garlic served as pest repellent. Lavender hyssop, lemon balm, mint, and sorrel appreciated growing in tomatoes’ shade. Tall marigolds attracted bees and other pollinators.
Seed Sowing, Transplanting and Staking Tomatoes
I experimented with different seed sowing methods indoors and outdoors. The winner: sowing and growing seedlings outdoors in plastic egg containers. Egg cup depth requires little soil. Sow two seeds per egg cup. Thinning to the strongest seedling in each cup.
The egg containers repurposed as mini greenhouses kept the air and soil reasonably warm for seed germination. Having separate cups prevents the delicate roots from entangling with other seedlings. Which makes transplanting easier and less of a surgical operation. Minimizing damage to seedlings’ fledgling root system means less recovery time after transplanting.
Seedlings don’t compete for sunlight in egg cups versus growing in clumps in a seed tray. I’ve never raised emaciated, weak stemmed seedlings in egg cups.
If sown in mid to late March, the seeds reliably germinated. I skipped the hardening off seedlings hassle. Read the winter sowing guide for details.
Root development is visible in clear egg cups. (You can transplant when the seedlings have one or two sets of true leaves. I’d wait until roots fill the cups).
Healthy roots, healthy plants. I transplanted seedlings into small pots for continued root growth. At about six to eight inches tall, the plant's final home was the large pots. I covered the pots with bird netting to protect them from digging critters.
Foot tall tomato plants were loosely tied to a bamboo stake or dried hydrangea stems for support. As height increased, stems thickened and fruit developed, I tied plants to sturdy wooden stakes.
Three large pots each one growing three tomato plants. PVC pipes support the young plants now. Later, bamboo canes and sticks inserted into the holes will provide additional support.
A closeup view of young plants growing in a large pot: tomatoes, marigolds, scallions and lavender hyssop. Lavender hyssop is a vigorous self sower.
Feeding and Watering Tomatoes
Organic gardening is how I garden. Weary of spending money on expensive organic feed such as worm castings, I concocted my own.
Growing Medium
A mixture of compost and potting soil filled the pots. The average potting soil drains and dries out too quickly for vegetable growing. Plus, these pots sat on a hot cement patio, making them prone to dryness.
To avoid soil compaction, I added crushed eggshells into the growing medium. The eggshells added calcium and other minerals. I had plenty of egg shells: I used 3-5 eggs daily.
Fertilizing
I was sparing with fertilizers. Pushing plants with fertilizers for production’s sake is unwise. Overfertilizing produces abundant, tender growth that appeals to pests. The results: an exhausting cycle of pest and disease control. For what? A few more tomatoes? It’s not worth it.
I diluted a liquid nitrogen feed made from grass clippings and water or dissolved alfalfa tablets in a gallon of water. Then switched to powdered eggshells dissolved in water when flower buds formed. Don’t expect pleasant scents.
If you want to be an organic gardener but you’re put off by the smell of organic fertilizers, then… I don’t really have any advice. Sorry.
Watering
Just when it gets hot and humid, it’s watering time. After the summer solstice, in Washington, DC it’s humid but rainfall is sparse. I rarely watered with a hose, preferring water from rain barrels.
Watering. My least favorite chore. During the dog days of summer (early July to mid August), I switch to watering at sunset. Water doesn’t evaporate during the hot day. And I don’t pass out in the heat. Plants don’t go to bed thirsty; they wake up the next day fully hydrated.
Pruning and Pinching Tomatoes
Gardeners prune indeterminate* tomato varieties. Pruning scared me. I’m not risking a tomato plant’s life at this stage. Nope.
You’re supposed to pinch all the suckers** below the first flower cluster. I don’t think I ever pinched consistently. I don’t think I noticed any difference in productivity. Though I wish I’d done both for an informed conclusion on the practice’s effectiveness.
Read How to Prune Tomatoes on finegardening.com for detailed advice on pruning and pinching tomatoes.
*Indeterminate tomato plants continue to grow stems, leaves and fruit throughout the growing season. Determinate plants have a vegetative growth phase then a flush of flowers and fruit. Plants cease growing as fruit ripens. Determinate tomatoes ripen all at once.
**Suckers are side shoots that form in the crotches or axils between the leaves and the main stem.
Tomatoes in various stages of ripening.
Grow Tomatoes… And There Will Be Pests
Luckily, I didn’t contend with many pests. My secret? Don’t grow fennel, carrots, parsley, dill or their kin near tomatoes. Some books suggest these plants are good tomato companions. My experience contradicted this advice.
Black swallowtail butterflies seek plants in the parsley family to lay eggs. Caterpillars eat parsley, et cetera and move on to devour plants in the nightshade family. Like tomato plants.
I recommend flowers/herbs that attract bees: tall marigolds, lavender hyssop and yarrow. (I hear borage is especially good; I haven’t tried it). Pollination increases. Garlic and onions repel insects.
For a few seasons, the hot patio suffered from spider mite infestations. Keeping the humidity high was challenging…and taxing.
My skink allies ate all the spider mites AND an infestation of leafhoppers. Ahh…the beauty of organic gardening and gardening with nature. Your pest is another creature’s food. Humans aren’t the only ones who value organic food.
Squirrels loved the soft, deep soil of the large pots. Black walnuts, acorns and hickory nuts turned up when refreshing the potting soil each spring. Covering pots in bird netting clasped tightly with binder clips curbed the digging. But those damn squirrels will get in through any gap or slack. Diligence is a must.
Something else annoying about squirrels. If it’s a dry year, they will take ONE bite out of a tomato and discard the rest. Squirrels, the cute menace.
Eastern Carpenter Bee gets deep in a Marigold 'Crackerjack'. She'll rest here before moving on to tomato, pepper, cucumber and eggplant flowers.
Marigold 'Crackerjack' is one of my favorite flowers: attracts pollinators, long blooming, good for cut flowers and easy to grow from seed. I bought a seed packet of mixed yellow shades for $1. I collected seed from those flowers for years. A useful flower for pennies.
Tomato Blossom End Rot and Tomato Blight Might Be Beyond Your Control
I was on top of my game. Proper watering and feeding prevented blossom end rot. Blight’s another story and harder to control, if not uncontrollable.
Tomato blight*** and blossom**** end rot arrived with erratic weather in Washington, DC. Both of these diseases flourish when temperatures and rainfall are unstable.
One summer, it didn’t warm up until late June. That July 4th had a high of 75 degrees. One summer, it rained most days. Another year, sparse rainfall.
Hard times for heirloom tomato growers.
Seed catalogs and plant nurseries market tomato cultivars as blight resistant. Resistant is emphasized. No tomato is immune.
*** Tomato blight, a fungal infection called Phytophthora infestans, spreads by wind and water-splash Ripening tomatoes develop brown sunken spots, which spread to the leaves and stems.
**** Blossom end rot is caused by lack of calcium in the fruit. Though the soil has plenty of calcium, drought stress, alternating soil moisture extremes, waterlogged cold soils and damage to a plant’s roots can all inhibit calcium uptake.
An almost ripe Tomato 'Illini Star.'
Tomato 'Illini Star' is a small garden's friend. Look at all those promising tomatoes!
Harvesting Tomatoes
Indeterminate tomatoes ripen throughout the season for daily picking. Now that I’m older and wiser, I’d grow a determinate variety to dry or freeze . I only knew canning as a preserving method (recently learned of freezing’s possibilities). I wasn’t canning in the heat of summer. No, thanks.
Tomato season’s end is sad. But one must accept that tomatoes stop outdoor ripening in late September/early October. That’s zone 7a.
Pick the green ones to ripen inside or make jams, chutneys and relishes. And, of course, fried. They’re still better than what’s in the grocery store.
Tomato Seed Sources
I'm not affiliated with these companies. I've purchased tomato and other seeds from them over the years with good results in Washington, DC (zone 7a). All have online catalogs.
Baker Creek Heirloom Seeds: pages and pages of color photographs of common and obscure tomato cultivars.
Southern Exposure Seeds: based in Virginia, this catalog offers tomato varieties suited to gardeners in zone 7a.
Botanical Interests: beautiful illustrations with a good selection of heirlooms and newer cultivars.
