Posted: 08/07/2012 at 08:28
Why are you watering them so much-this is the problem-there is a tomato expert on this forum-italiophile-who constantly says they need tough love to grow properly.
Easeback on the watering-let them dry out-remove some of the yellowing leaves -only a few -not all and they will be fine
Just not so much water.
Geoff is right. The biggest mistake you can make with toms is watering by rote - automatically, regardless of conditions. The rule of thumb is simple: water toms when they need it. When do they need it? When the mix - in the case of containers - dries out. You can let the mix dry out. It will not hurt the plant. Leaving the mix dry for a week obviously will hurt the plant but over a day it won't.
There's a myth that toms are delicate plants. They're not. By nature, historically, genetically, they're tough, robust individuals that will survive in adverse conditions. Watering a tom in a container once a day - let alone twice a day - amounts to overwatering. Here's a case in point -
Every year I give our (now) 8 year-old neighbour, Ettore, a tom in a pot. He loves gardening, he watches me from his window in my orto (vegie garden) and, one day, wants to help me. His care for the tom amounts to counting the fruit. His mum, Paola, does all the work. This year it's a Camp Joy (aka Chadwick's Cherry) cherry in a relatively small container.
Now, they have no garden at all. The plant lives outside their front door. It gets about 6 hours a day of full sun. And the temperatures have been in the mid-30s for the last month. Paola waters her window boxes every day. I've had almost to break one of her arms to stop her watering the tom every day. Even 6 hours a day of direct mid-30s sun doesn't completely dry out the mix in a day.
She asked me why the leaves were yellowing. I told her the roots were constantly damp. She was over-watering. I told her that toms aren't flowers in a window box. They're a different beast with different requirements. I got her to stick a finger deep down into the mix. Sure enough, deep down, where the roots are, the mix was damp.
Finally, I've got her watering every second day. The yellow leaves are disappearing and the plant is starting to fruit.
Many of the problems that arise for the home tomato grower come about when the plants' natural sturdiness is overwhelmed by pampering - over-watering and over-feeding. Pampering a tomato plant doesn't strengthen it. It weakens it. An over-watered and over-fed plant is more vulnerable to disease and other problems.
In simple terms, producing fruit is a plant's means of reproducing itself. Tomatoes will feel more inclined to reproduce themselves if they feel ever so slightly threatened. It's their inbuilt survival mechanism. That's what you need to exploit to maximise production. Call it what you like - tough love, controlled neglect - but it's the exact opposite of pampering.
As lilylouise rightly says above, irregular watering is thought to be one of the factors contributing to Blossom End Rot - no one actually knows for sure - so the watering pattern needs to be regular. That doesn't have to mean every day. It means establishing the plant's requirements and watering - app