THE EFFECT OF THE NUTRIENT CONCENTRATION IN THE PROPAGATION OF TOMATOES AND CUCUMBERS ON ROCKWOOL

In November 1984 the members of the most important Dutch vegetable auctions were asked, as one of the questions in an inguiry, what their expectations were with respect to the planting of tomatoes and cucumbers,-on rockwool and in soil – in the period from December 1984 till April 1985. It appeared from the results that there were plans to plant 1774 ha tomatoes and 561 ha cucumbers.
Slightly more than 50% of the tomatoes (901 ha) were to grow on rockwool. 352 of the 561 ha cucumbers (61%) would be planted on rockwool.
The expectations in November 1984 of ca 1250 ha tomatoes and cucumbers on rockwool, have been on the conservative side.
At the moment (May 1985) it is assumed that the acreage is ca 1500 ha.
In the years behind us it has become clear that the propagation of plant material has to be adjusted to the growing system.
In other words, if growing is to take place on rockwool then the plants have to be raised on rockwool as well.

In the propagation on rockwool the concentration of fertilizers is an important factor in growth and plant quality.
At the Research Station at Naaldwijk the effects of increasing ECs of the nutrient solution have been studied more closely.

Symposium on Nutrition, Growing Techniques and Plant Substrates

G.A. Boertje

https://doi.org/10.17660/ActaHortic.1986.178.6