Give your seedling transplant TLC

From emergence to pulling, seedling growers spend five to eight weeks providing their seedlings with daily care. Farmers usually provide good care once the transplants are planted and irrigated, but there is a weak link – transplanting.

Before the introduction of the Speedling system, farmers would use bare root seedlings which were pulled after hardening and irrigated the previous day. This process left most of the root system behind in the soil, causing much transplant shock. The plant would take days to recover. Often the first priority was just to keep the transplants alive.

The root wounds also admitted pathogenic organisms. The only advantage was that the roots were in close proximity to the soil, and some soil would cling to the roots during transport. Once planted, however, the plant would spend its energy reserves growing new roots and therefore, with the correct treatment, the plants would grow well. The Speedling system eliminates root damage caused at pulling and reduces transplant shock. However, farmers complacent about the new system miss out on its full benefits. Seedling growers are also at fault when they send farmers hardened plants in a fully dormant state. Though this hardening is necessary for the survival of the seedlings, these plants won’t perceive the need for root development. If hardened by withholding nitrogen, they won’t have much energy either.

In such cases it is economical and benefits both parties if the seedling grower doses the plants with nitrogen before they leave the nursery, perhaps even a few days before pulling if the collection date is certain. Alternatively, the farmer can use one handful of limestone ammonium nitrate per watering can and irrigate the seedlings before transplant. At transplant, the seedling’s plugs should be very moist. This protects the fine root hairs. Preserving these fine roots helps the plant to grow rapidly and ensures uniformity. In stressful conditions the soil needs to be moist and irrigated as soon as possible. It is also important that seedlings aren’t handled roughly at planting.

This can shake the medium off the roots, or bend them, causing deformed, J-shaped roots. These small details can massively influence yield and uniformity. Some farmers swear by mechanical planters for a runt-free, uniform stand. But actually, they’re admitting they weren’t paying attention when planting by hand. With a few hours’ work and at no extra cost, correct supervision can make a big difference to a harvest. Contact Bill Kerr on (016) • 366 0616.