Cultivation of young plants in the greenhouse
Besonders deutliche Verfrühung erzielt man durch Anzucht frühreifender Sorten im A considerable earlier harvest can be achieved by growing young plants of early maturing varieties in the greenhouse before planting them on the field. The young plants can be put in almost all common substrates for young plants. The quantity of the substrate per plant unit should be sufficient for two – three weeks. Paperpots and plastic pots can be used (clay pots are not suitable as they might break when the plant develops strong roots). Too high temperatures in the greenhouse cause early flowering and at the same time lead to too low vegetative development so that, on the field, the plants and ears remain too small. The average temperature should be aprox. 12 – 15 °, air condition should be adjusted to 20°.
Corn shows very positive reactions on the application of mulch, perforated plastic or fleece for the protection of young plants. Especially fleece has proved successful. By accelerating the warming up of the soil and reducing the germination period the harvest is advanced by aprox. 14 days in comparison with uncovered plants.
Combination of measures
The above mentioned measures can also be combined. Thus, it is possible to cover populations with fleece, and the harvest of direct sowings can be advanced by the application of mulch or fleece. Fleece (17 gr/ m2) can remain on the field until the plants are knee-high, but it must be large enough to give the growing plants enough room.