How to Grow Tomatoes and Other Vegetables in Containers

Written by Greenwise Team
Published on May 10, 2013
We came across the following article in The Big Blog of Gardening, one of our favorite and most useful blogs about “organic gardening and organic lawn care tips. Delicious vegetables, a green lawn and beautiful flowers without chemicals.”. After reading the entry, we had a “we couldn’t have said it better ourselves” moment, so we’re reprinting the article in its entirety. Thanks to the author, Todd Heft, and our friends at The Big Blog of Gardening. And be sure to check out their site!
Posted by Todd Heft on April 13, 2013 on The Big Blog of Gardening Alright, so you don’t have a massive yard to build the garden of your dreams (or my dreams, perhaps). Or maybe you just don’t have the time, energy or inclination to do all of that garden prep work. But you love fresh, garden tomatoes and who could blame you? Supermarket-bland tomatoes aren’t good at any price. The good news is you can enjoy fresh tomatoes by growing them in containers in a sunny area outdoors – a patio, apartment balcony, porch, deck, or even in containers placed around your yard. Cucumbers, squash, strawberries and peppers are popular container plants too, as are potatoes, artichoke, leaf lettuces, celery, eggplant, snap beans, peas, and most herbs. So depending on how ambitious you are, you can grow most of the fresh garden vegetables you love only a few steps from your door. Let’s define containers – I’m talking about anything from a soup can or windowbox to a 48 inch wide and tall container made from plastic to look like an old-fashioned terra cotta pot. Containers can also be made from plastic storage bins, cans which contained food, plastic or metal buckets, old watering cans, whatever your imagination suggests. The only definitive criteria is that the container was never used to store toxic chemicals (including oils, greases, paints and varnishes), it’s deep enough for the roots of the plant it will be home to, and that water can drain from the bottom of it. If the container doesn’t allow for drainage, you run the risk that the roots of the plant will rot. When you go to your local garden center to choose seedlings, be sure to read the plant tag very carefully. If you’re just starting container gardening, go easy on yourself and look for dwarf varieties or those bred especially for containers – these plants will grow smaller than garden varieties and will be easier to manage. If the plant tag says its a “determinate” variety of tomato, that means all of the tomatoes on that plant will mature within a week or two of each other – great for canning or making sauce. Tomatoes which are indeterminate will produce fruits until frost. Most determinates grow like a bush, and indeterminates grow like a vine which you’ll have to train vertically on a trellis, railing, or some other structure to give it support. Also check the tag for mature height – if the indeterminate grows very large, like 12 feet, pass on it for a more compact variety which doesn’t exceed six feet. How much sunlight? Container vegetables need about eight hours of direct sunlight each day. Any less, and growth and fruit yield will be reduced. If necessary, move containers around during the day to take advantage of sunny spots. A south facing porch, deck, or patio is best for maximizing sunlight, and keep the plants out of the shadows until late in the day. Did you know that sweet peppers can be grown as perennials if protected from frost? If you don’t live in a frost-free area, but your home has a very sunny room, bring the pepper plant indoors over winter and re-pot it each spring. What kinds of containers? The rule of thumb is the larger the container is in relation to the plant, the more production you’ll get. Personally, I love clay (terra cotta) pots for their aesthetic, old school appeal, but they do dry out faster than plastic, which require less watering. If you’re creating your own containers, make sure you drill drainage holes in the bottom or the roots of the plant may rot. If you have an old window screen laying around, use a piece of it inside the pot over the drainage holes to keep soil from washing out and to keep pests from crawling up and in. And make sure that your containers are neutral or light colors – dark brown or black will absorb solar heat and the roots of the plant may become too warm, especially if your season is particularly hot. Use as large a container as possible to allow for sufficient root growth, because if you restrict growth on the bottom, you also restrict growth on top. Container Soil Your container growing success largely depends on your potting soil. Don’t use garden soil alone, because it will compact after a month or two, becoming hard as cement. This will seriously diminish fruit production if not kill the plant because water won’t get to the roots. Garden soil may also contain insect or bacterial pests which will be difficult to control in containers. The best choice is a loose soil which drains quickly and is high in organic matter. The mix should be one part each potting soil, perlite, finished compost, and sphagnum peat moss – but be careful with the peat moss, because adding too much will allow the soil to compact. Make sure the compost has been professionally “cooked”, like bagged compost from garden centers, so all weed seeds and pests have been killed. And fill the pot all the way to the bottom with soil – assuming it’s not a tiny plant in a huge container – don’t place rocks or other items in the pot to save soil, because your plant’s roots will need every bit of it. If the plant will require staking or trellising, add the support to the pot when filling the container so you don’t damage the plant’s roots inserting it later. The support itself may also have to be anchored to a permanent structure like a railing so that wind doesn’t take your tomato plant for a short ride to a hard surface. Feeding and watering container plants Your container plant’s access to water and nutrition will be limited, it being in a container and all. Unlike garden plants, its roots can’t plunge deep in the soil, going wherever they please. Container vegetables need some help, so a small amount of organic fertilizer applied weekly is required. You can also opt for a slow release organic fertilizer which you add when planting, which should work for about one month. When they’re producing fruit, tomatoes like to be fertilized a little at a time instead of in one large feeding, so after the first month, start feeding weekly with a liquid fertilizer like fish emulsion. Vegetables grown in containers will also need more frequent watering than those grown in the garden, typically each day, so keep an eye on the moisture level in the soil. Don’t wait for signs of your plant being thirsty before watering – at that point you’re behind the curve. Stick your finger in the soil up to your second knuckle once each day – if your knuckle doesn’t come out damp, it’s time to water. Give it a good, deep soaking each time, not a surface spritz, because if the tomato plant is under constant water stress, there’s a good chance it will develop blossom end rot. I also place a light mulch of shredded bark on top of my container plants to slow evaporation. According to garden author Doug Green, “The number one rule in growing containers, whether they are hanging baskets, small houseplant pots or giant whiskey barrels is that every time you water the pot, you continue watering until at least 30% of the water has gone out the bottom of the pot.” Recommended Container sizes for vegetables Peppers and dwarf varieties of tomatoes: 2 gallon pots Full sized tomatoes and cucumbers: 5 gallon pots Salad greens, onions, beets: pots 10″ in diameter Most herbs: 6″ diameter pots Best varieties of tomatoes for containers Bush Early Girl Patio Princess Sweetheart of the patio Balcony Window Box Roma Marglobe Bushsteak Baxter’s Bush Cherry Super Bush Hybrid Tumbling Tom Yellow Stupice Sweet Baby Girl Gardener’s Delight Tumbler