August is the month of maximum tomato excitement as warm days and nights ripen the fruits. Keeping your plants in good fettle is a top priority.
The soil needs to be moist at all times, but never too much water at a time. Too much makes the fruits split, too little and you get blossom end rot and a host of stress related diseases.
Using slug pellets and other insecticides gives rise to insect problems, as pellets kill many other insects as well as slugs, such as ones that eat slug eggs, whitefly and red spider mite. For the first time in years I have some whitefly on two tomato plants, so I have given them a little extra water and the fly population is already decreasing. Lack of water weakens the strength of the plant walls and this allowed the fly to establish. I have noticed a large number of ants crawling on these two plants and many extra cobwebs.
It is all about getting the water balance right, and a matter of reasoned guesswork. Visiting other gardens it seems that most people grow tomatoes in bags or pots, which makes minute control critical. Watering a bag in the morning is not enough, as its limited root system will be unable to supply enough water on a hot afternoon and you will get blossom end rot, or possibly no fruit set at all. Plants grown in deep soil with a rich mulch of compost holds large supplies of water available when the plant most needs it.
And then there’s the dreaded blight. From now only water the soil, keeping the leaves dry. Reducing water stress is again paramount: cutting out the growing tip and reducing the number of fruit trusses lowers stress levels on the plant. Encouraging a gentle airflow around the plants helps, so remove the lowest sets of leaves. Even so, our plants evemtually get blighted in October, by which time the warmth and day length the plant needs is just not there. Removing many of the greener fruits helps, and we find that the cherry tomatoes such as Gardeners Delight are less susceptible.
For outdoor plants blight is even more of a problem. It helps to grow them in a sheltered area against a building and underneath a roof gutter, which keeps most rain off the leaves.
And why did the tomato go out with a prune? Because she couldn’t find a date.
Sowings this month
Turnips, spring cabbage, rocket, oriental leaves such as mustards, Little Gem lettuce. You can risk last sowings of chard, spinach and radicchio early on.
In the greenhouse sow oriental salad leaves and lettuce, potatoes for Christmas.
