Damaging frosts have pillaged much of the country, impacting crops that have already been planted. In response, farmers may light smudge pots, run windmills and use irrigation water. Other practices, such as foliar applying Osmotech or Drammatic Fish to lower the freezing point of plant tissues, may be used if a grower has these products on-hand.
Regrettably, often a grower can’t do much but wait for the freezing temperatures to pass, then assess the damage and decide whether or not to replant. These decisions are usually well guided by extension and local expertise.
Replanting corn may be an exception to that rule. The growing point of corn remains well inside the plant until the plant is several inches tall. Some of you may not be too concerned as your corn’s growing points are still below ground, thus protected from the frost. Still, the corn tissues above ground that die will become a physical barrier to new growth. These dead corn tops will dry out, get tangled and choke off new growth. Or worse, they may start rotting and take the live tissue with them. For corn crops that die back to the ground, you need a really good reason not to replant.
This article, however, is not about what could have been done. It’s about what can be done for the survivors. Annual crops that survive will have lost momentum. Even peas and cole crops experience stress if it’s cold enough. Perennial crops like alfalfa will start growing again from the crown but the damaged tissues will grow no further. This puts a lot of stress on those crops because new growth is fueled primarily from stored reserves within the plant, and the plant has already spent a great deal of its stored energy on the frosted tissues. Potatoes can also be badly affected. Frost damage can lead to seed piece decay for plants still relying on the seed piece for energy. This can lead to loss of set.
Reenergize these crops with foliar fertilization.
- Replace the minerals that are practically lost in the dead or damaged tissues (N, P, K and traces) with products such as Accelator, TracePak, MicroTech AG and Micrel Total. (One’s trace package will change depending on the crop.)
- Incorporate antioxidants such as Drammatic O Fish to directly counter these abiotic stresses.
- Reinforce the spray with the beneficial bacteria from SP-1. The good microbes that live in partnership with plants, below and above ground, got hammered too.
- Do so in a gentle manner. These plants are injured and should be nursed. All of the products mentioned above are in this category.
- Wait to apply these products until after the plants have started to grow back out of frost damage. It does little good to apply foliar nutrition if the plant is unable to take it in or use it.
Preemptive action ahead of stress events should be taken to minimize damage. In regions where the problem is common, it’s wise to keep products on-hand that may mitigate damage. After the fact, it is very possible that some sustained damage can be undone. You may need to replant, or it may be in your best interest to apply a foliar fertilizer to regain the momentum.