Growing tomatoes in containers is almost always an adventure. It can be incredibly rewarding, or flat out disastrous – sometimes for reasons beyond your control. But there are some common mistakes (trust me, I’ve made most of them, often more than once) that if you avoid them, will increase your chances of growing tomatoes in containers successfully.
Small Containers:
When it comes to tomato containers, bigger is better. The bigger your container, the more soil it will hold. The more soil you have the better the moisture retention and the more available nutrition will be to your plants – both of which are critical to happy, healthy tomato plants, and large harvests.
Too Much Water:
Watering your tomato plants properly is probably the main key to tomato success. Too much water and the plants drown, too little and you get blossom end rot. Inconsistent watering will get you blossom end rot, split tomatoes and stressed plants. You want to keep the soil in your pots consistently moist – not wet, but damp. Before you water, check if your soil is already moist. To do this put your finger into the soil about an inch. Water if the soil feels dry to the touch. Don’t forget drainage too. Make sure your pot has large holes in the bottom so excess water can drain out. Pot feet are also a good idea if you have your pot on a patio or non-porous surface. Another great way to control water to your containers is to use a grow box. I’ve had great success with Earthbox and The Grow Box brands. For more info on keeping plants from drowning.
Too Little Water:
The amount of water your tomato plant needs will depend on heat, humidity, the size of your pot and the kind of potting soil you use. By mid-season, a large tomato plant may need watering at least once a day – sometimes twice. Also, when you water, make sure to really soak your plants – if you just give them a sip, the water will only wet the top layer of soil. Water until you see it coming out of the bottom of your pot. When you water, try to water the soil directly, not the leaves, because wet leaves can lead to fungus.
Don’t bother with water crystals they are expensive and tests have shown that they aren’t particularly effective. Overcrowding:
Putting lots of plants in one pot may seem like a good idea, but it usually is counterproductive. Unless my pot is tremendous (more like a raised bed) I only put one tomato plant per pot. To get an idea of minimum size, I have successfully grown one huge tomato plant in large reusable grocery bag and that’s about as small as I’d go per plant.
Not Enough Sun:
Tomatoes are sun lovers and need full sun – which means that they need unobstructed, direct sunlight for 6-8 hours a day – no cheating or skimping. Many people (myself included) chronically overestimate how much sun an area gets. Really figure this out – either with a watch or a sunlight meter – before you plant up your pots.
Chilly Tomatoes:
Along with sun, tomatoes like warm temperatures. While it might feel like you’re getting a jump on the season by putting your tomatoes out early, they will not really do anything until it is consistently warm. If you do want to get a jump on the season, you can either cover your tomatoes with cloches, or plastic when it’s cold, or do what I generally do which is to put them on carts and wagons and haul them in and out of my garage until temperatures warm up. Also, don’t forget to harden off your seedlings.
Starving your plants:
Tomatoes are heavy feeders and need to be fertilized, if you aren’t using a pre-fertilized potting soil. Most potting mixes has very few of the nutrients that your plants require to grow and be healthy so you will need to add those nutrients to the soil, or stimulate the ones already there, if your mix is heavy on compost. There are many fertilizers to choose from but I use either an all-purpose organic slow-release fertilizer, or one designed especially for growing tomatoes or vegetables, which I mix into my potting soil. In addition, I use a diluted fish emulsion/seaweed liquid, once every week or two.
Choosing the Wrong Variety of Tomato:
I disagree with conventional the wisdom here that suggests tomatoes with “patio,” in their name. I think that most patio tomatoes taste, well, more like patio pavers than tomatoes. I love growing huge luscious tomatoes and sprawling cherry tomatoes. To me tomatoes are all about taste and texture and I don’t want to bother growing them if they aren’t totally delicious. Here are some of my favorite tomato varieties.
Growing Tomatoes Upside-Down:
A lot of people swear by growing tomatoes upside-down. Not me. I have tried it several ways and haven’t found any to be all that great. I see the point of growing tomatoes that hang – just not upside down. If you want to know why, here’s an article on the Upsides and Downsides of Upside-Down Tomatoes.
Staking or Caging too Late:
This is one of my chronic mistakes. I always forget how fast tomatoes grow and don’t stake or cage them until they are huge and unwieldy. It is much better to set up your cages or stakes before your tomatoes get too big. Here is a video on how to build a bamboo tomato cage .
Original article here