Greenhouse Tomato Growing Tips
The tomato is undoubtedly the most popular of all greenhouse food crops, and very few home greenhouses are without them. However, a common mistake is to grow them in the ground sod of the greenhouse.
This is all right when the house is plastic and can be moved to a different spot on the vegetable garden each year, but not when the house is permanent and the same soil has to be continuously cropped. This is because the tomato soon suffers from ‘soil sickness’.
On a particular soil, a good crop is usually obtained the first year, but afterwards pests and diseases, and other troubles resulting from an over-used soil; soon cause serious deterioration. Some growers like to change the soil each year, but this is laborious, not always effective, and unnecessary.
It is far easier and more reliable to grow the plants in pots or other containers such as Grow Bags. The latter are plastic bags filled with a special compost which are put flat on the ground. Holes are cut in the side through which the plants are planted.
Ring culture is also popular. In this method bottomless rings made from fiber are set on a layer of peat or grit kept moist with water. The tomato compost is put in the rings, such as Charlie’s Compost, John Innes No 3 (for folks in the UK), or any proprietary potting compost, and the plants. Only the rings arc given liquid feeds, but should they dry out they must be re-moistened with water.
If the peat or grit layer is kept constantly moist, the compost in the rings should take up water by capillary action. The layer should be spread on polythene sheeting and be about 10-15cm/4-6in thick. The rings are usually about 23-25cm/9-10in in diameter.
The theory of this method is that the fine fibrous roots that form at the top of the root system more readily take in liquid feeds, and the basal roots the plants needs for water.
When this method is employed, there is less trouble from cracked skins, and flower and young fruit drop—common when small pots are used and moisture conditions at the roots vary widely between dry and wet.
The plants should be trained up strings or canes by twining them around the support in a clockwise direction. All shoots, except those carrying flower buds, that form where leaves join the main stem must be removed as soon as this can be done without damage.
When cropping, the temperature of the greenhouse must be kept preferably below about 27°C/80°F, or the red pigment in the fruits will not form properly. There will then be trouble from ‘greenback’ and blotchy ripening.
To aid pollination and a good fruit set, spray the flowers with a fine mist of water each morning preferably when conditions are bright and warm.
For shading use a white shading paint on the outside glass. Heavy shading and green shading should be avoided. It is easy to raise your own plants from seed. This also allows a wide selection of varieties which experienced seed vendors describe in their catalogs.
Greenhouse Chrysanthemums Growing Tips
Late flowering chrysanthemums are splendid as a follow up for tomatoes, since while the tomatoes are cropping they can be grown on outside. They need greenhouse protection only from autumn onwards.
There are very many different chrysanthemum types, and they may bear numerous small flowers or a few extremely large ones. Most greenhouse types need training like stopping and disbudding. These operations are not difficult and a catalog from any leading specialist will give full explanation.
A catalog is a further essential, because the stopping times can vary with each variety. The stopping and disbudding is done to obtain the best quality flowers at the right time. The plants are sold as rooted cuttings, and they should be potted up from February to March using 13-15cm/5-6in pots of Charlie’s Compost or John Innes No 3 compost.
At first, the plants can be kept in a frost-free greenhouse or frame. By June, the plants can be given 20-23cm/8-9in pots and stood out in the open. Choose a place sheltered from wind, but take precautions to see they are well secured so that they don’t blow over as the plants become sizable.
Canes and wires will be needed for support. Keep the plants well watered and fed and transfer to the greenhouse about mid-September for flowering.