Agriculture Reference
In-Depth Information
Crop row
secondary
passage
N
Crop row
secondary
passage
N
Crop row
secondary
passage
N
Fig. 12.5.
Usual arrangement of the main passages in a greenhouse.
in the peninsular type (around 75%).
Another arrangement, which is more
expensive, is that of semi-mobile rolling
trays which can be moved (Fig. 12.7), but
allow for a greenhouse occupancy rate
from 85 to 90%.
The passages are usually between 40
and 50 cm wide and the bedplates or trays
1.6-2.0 m wide, accessible from both sides.
The use of crop frames, with the aim of
increasing the occupancy rate, generates
different microclimate conditions between
plants, possibly limiting the PAR available
to the plants (Photo 12.4); the profitability
of its use is questionable.
In ornamental crops, the location of
several lines of pots at some height allows
for increasing the occupancy rate by
10-20%, although care must be taken not
to cause excess shade (Berninger, 1989).
There are other mobile or fixed devices,
which allow for placing a higher number of
pots inside the greenhouse but which are
only of interest in species of low light
requirements (Photo 12.5).
An important aspect to be considered
in non-conventional arrangements, is the
notable differences in microclimate that are
generated, not only in light but also in
temperature.
