GROWTH OF SEEDLINGS OF CAULIFLOWER AT DIFFERENT TEMPERATURE AND CONDUCTIVITY IN WATER CULTURE

Background for the following results is as follows.
In spring 1981 several growers of cauliflowers had failure of crops when the bedding plants were moved outdoor from glasshouses for acclimatization.
This was specially seen when the plants were moved out on a day followed by severe night-frost, with bright sunshine the following day.
The bedding plants became small and stunted.

The seedlings are normally raised in soil blocks made of a mixture of clay and peat, this mixture varies from grower to grower.
The ratio of clay and peat has great influence on the water capacity of the soil blocks and their capability to retain water when drained or exposed to sunshine, wind etc.
This again could be assumed to affect the saltconcentration at the roots of the plants.

The capability of the soil blocks to retain or emit water can be expressed by the retention curve, which can be determined by means of the equipment shown in fig. 1 (Willumsen 1972).

Fig. 2 shows the retention curves for soil blocks with or without admixture of clay.

Symposium on Timing of Field Production of Vegetables

H. Hansen

https://doi.org/10.17660/ActaHortic.1981.122.13