Many vegetables, particular tomatoes, lettuce and cabbage are grown on vast scales within the Central Valley of California. Rather than being sown, they are transplanted after starting life in a controlled environment, or greenhouse. Our Nuffield group spent the morning with Westside Transplants at their Firebaugh depot near Fresno to find out more.
Vegetables grown from transplants can be harvested earlier than those grown from seed. Growers who use transplants can target early season markets and reduce the time needed to produce a crop, allowing them to produce a second or third crop during a single growing season.
Transplants grown in the greenhouse can be protected efficiently against environmental stress, disease and insect pests. Transplants can allow growers to establish near perfect stands, allow for optimal spacing and uniform plant age once transplanted within the field. On our tour of Westside Transplants, we saw both tomatoes and melons being grown under controlled environments.
Where the costs of seed is very high, the use of transplants can actually reduce the costs of establishing a vegetable crop because less seed is used and the need for thinning and early weeding is eliminated. Transplants also allow more efficient use of fertiliser and irrigation water during early growth stages.
The successful production of transplants requires sterilised growth media, temperature and light control, effective pest and disease management, along with appropriate sanitation practices. Transplanting is both labour and capital intensive, so economies of scale is necessary, but when the plant success rate and uniformity of cover and harvest is taken into account, the financial benefit on sale of produce can easily outweigh the ‘traditional’ seed sowing methods.
When seedlings are moved from the greenhouse to the field, they undergo transplant shock (a setback in growth). How quickly a plant overcomes this shock and establishes itself in the field depends on plant type, environmental conditions and the quality of the transplant.
Different plant species vary greatly for the suitability for transplanting. A plants suitability is determined by the speed with which it can regenerate roots that are damaged during the transplanting and re-establish normal roots. Vegetable species that are ideal for this process are tomatoes and melons.
Tomatoes and seedless water melon for transplanted on a huge scale each year with thousands of acres being planted within the Central Valley on an annual basis. We were lucky enough to see tomatoes being transplanted.
It would seem to transplant, rather than to seed is the way forward…….