Straw bale culture of tomatoes

Press, Volume CXII, Issue 33034, 29 September 1972, Page 14

Straw bale culture of tomatoes

Tomatoes and cucumbers can be grown successfully under glass almost continuously throughout the year, providing that certain conditions are met and the grower is prepared to give adequate attention to management. In this respect one of the biggest problems which can eventuate with time is soil infection. This can be fairly well overcome by sterilisation of the soil either with steam or by chemicals. Another way is to replace the soil to a" minimum depth of 12in. Each method has its distinct advantage and associated problems and to be a success must be executed properly. A method which may have some appeal, and which is used on a commercial basis, is straw bale culture, a system which was evolved because of the increasing difficulty experienced in England in getting horse manure, an ingredient of a formerly traditional method of raising these crops. Initially, it is necessary to form a shallow trough, say 2 inches deep, the length of the glasshouse and just wide enough to accommodate the bales. This depression is then lined with polythene, the material being brought up just over the sides so as to form a waterproof trough. The next step is to procure sufficient well tied bales of straw. It is absolutely

essential to use only those which come from paddocks which were not sprayed with residual hormone weedkillers such as 236 TBA, MCPA and picloram. The bales are put on the polythene and very thoroughly soaked. When saturated each bale must be topdressed with fertilisers which must themselves be watered in.

The following application a bale is required: l|lb nitrolime, 12oz potassium nitrate (saltpetre), 30oz serpentine superphosphate and 3oz ferrous sulphate. Rapid fermentation will occur and considerable heat will be generated, not to mention the possible release of ammonia fumes. During this development it is essential to keep the bales from drying out. When the temperature begins to fall planting can be carried out. Each bale should be topped with a little clean soil, just sufficient to hold the plants which will quickly root down into the warm straw.

Watering will demand close attention thereafter and as a general guide should be applied sparingly but often. Feeding must commence much earlier than usual and it is probably advantageous to resort to liquid feed once a week through the water supply. As the straw rots the bales will naturally sink pulling

the plants downwards in the 1 process. Care should be < taken in stringing the plants i to leave a little slack.

Under hot conditions, particularly in summer, the bales will dry out more rapidly and will therefore require extra attention.

Plants do well on this system because of additional

warmth created by the decomposing bales and the increase of carbon dioxide in the air from this source.

At the end of the season the rotted straw can be simply pulled out and utilised as compost in the garden. The house is then ready for

further use with the minimum of delay.