Generally, Broccoli matures earlier than cabbage or cauliflower. Early maturation is becoming increasingly popular, especially with pre-packed products.
Farmers rightfully reason that the quicker crops are harvested, the sooner they can prepare for the next crop and the more profit they’ll make.
Later varieties may have a higher yield potential, but if the heads are cut at a certain size for punnets, they can’t be allowed to reach full size. With early maturing, vigorous growth should be ensured right after transplanting. It is better to use seedlings that have not been hardened and to provide the correct soil conditions. Seedlings should be moist when planted and also planted in moist soil, preferably in the late afternoon.
Ensure that the first nitrogen topdressing is applied from three to five days after transplanting. By this time the roots will have started to grow from the medium into the soil and irrigations are now further apart. For hand dressing, use one handful of limestone ammonium nitrate (LAN) on 10 to 12 plants and make sure that it is positioned a few centimetres from the stems.
For high cost of labour, use a Mayfield applicator or a conduit tied into an empty fertiliser bag and run it down next to the rows. Some farmers just cast a fairly heavy application before irrigation. If you’re using band-placed fertiliser, a light application of only about 100kg/ha is required. The next application can be broadcast two weeks later in summer and again three weeks into winter. This is usually enough. Apply 200kg of LAN for the second application. Broccoli requires less nitrogen than cabbage, as farmers harvest 15 to 20 tons per hectare, whereas cabbages should exceed 100 tons.
The faster the crop grows, the more important it is to ensure that there is adequate water, especially in hot, dry weather. In such conditions the moisture content of the soil needs to be slightly higher than usual. The crop can also be cooled off by applying water to a large area.
There is a huge difference in microclimate when passing the windward side of an irrigated land, regardless of the moisture content of the soil. This is important during heat waves, especially when harvesting is only three weeks away. If farmers stick to these basics, the crop will be surprisingly easy to grow. – Bill Kerr Contact Bill Kerr on (016) 366 0616 or e-mail [email protected]. |fw