Double Stems and Side Shoots
Some professional growers allow a side shoot to develop and become a second main stem. This has the following advantages:
- More trusses
- Trusses at a lower height than if grown on one stem
- Plants are easier to prune and manage generally – unless you have a tall greenhouse and step ladder!
It’s best to use this technique with cherry varieties that are quick to mature if you are in a short season area such as the UK.
Larger varieties require more energy for growth – so increasing the number of trusses of large tomatoes grown using two stems, needs a very good Summer and is more challenging.
This side shoot could be left to grow and create a second stem if required … otherwise, it’s best removed. Side shoots are normally removed from tall varieties to keep one main stem.
You may notice the drops of water on the edges of the leaves in the photo above. This is called “guttation”.
When leaf stomata close at night and there is a build up of pressure in the plant, moisture is forced out of the leaf edges through pores called hydathodes. These are water glands that live near the vein endings in the tips of leaves.
Guttation is usually seen first thing in the morning after a night when stomata have been closed and it’s most likely to occur in the greenhouse in warm weather.
We’re Having a Heatwave
It looks as if we have a mini heatwave on the way – in the UK.
Although tomato plants like warm sunny weather, many of the varieties we grow in the UK don’t do well in higher temperatures and become stressed.
The general rule of thumb is – if it’s too hot to sit in the sun for us humans, it’s probably too hot in the sun for a tomato plant!
Here are a few tips for helping your tomato plants to cope:
Most container grown plants, especially those in hanging baskets, may need watering twice a day.
Keep your eye on plants watered in trays by the Smart Valve or by capillary action such as the Quadgrow Planter – some manual watering may be necessary.
It’s best to keep windows open in the greenhouse to avoid temperatures and humidity becoming too high.
Cool glass (similar to the old windowlene) can be used on windows to help shade plants. One or two sheets of garden fleece http://can also help to diffuse direct sunlight.
When Growth Stops
If temperatures in the greenhouse reach around 35C, sugar production in the leaves (photosynthesis) levels off, but plants continue to need more sugar for growth as temperatures rise. This can result in growth stopping and fruit losing its sweetness!
Feeding In Hot Weather
If using mineral feeds like Tomorite or Chempak, it’s best to reduce the strength of food given when the weather is hot.
Plants use a lot of water which usually evaporates through the leaf pores (stomata). However, the minerals remain in their system – reducing the amount of water that they can hold.
Also, the stronger the solution around the roots, the slower a plant is able to absorb water. So, on a hot day plants may wilt if overfed.
The best way to feed under normal conditions is to give half the amount recommended on the pack at every watering or every other watering – depending on the stage of growth.
However, being too generous may produce fruit that ripen before they reach full size, wilting in hot weather and Blossom End Rot – to name just a few problems.
If you are new to growing tomatoes this season, please don’t be put off by the possibility of so many problems and suggested tweaks. Chances are you’ll get a good crop by following the directions on the side of the pack!
This article “Double Stems and Side Shoots” was originally one of Nick’s Tomato Growing Newsletters.