Abiotic Damage: Cold

Abiotic Damage: Cold

Winter is in full swing here in Washington. Given the cold night time temps we can get in January and February I thought I’d talk about what cold damage can look like.

Abiotic -meaning without biology- damage can be really anxiety inducing, it usually happens suddenly and across an entire crop or entire planting. Look at your top stems and buds, these are usually the most sensitive and they will generally show the worst damage. Look for soft, water soaked stems and leaves. If you’re a few days out from the damage it can quickly become infected with botrytis or dry out and look brown. If you do have a botrytis outbreak remove dead stems or leaves otherwise it may spread to undamaged tissue.

Always ask yourself, about when did the damage occur, was the damage apparent immediately after it warmed up following a cold snap? Did this crop have soft or new growth late in the season? Is this crop inherently sensitive to cold? – I’m looking at you Fatsia-. If the answer to any of these questions is yes, you may have found your answer. Remember that few bacteria or fungi are significantly active when it is sub 40 degrees.

The good news is most plants recover fairly quickly from cold damage and a few quick prunes in spring prior to flush will help with aesthetics and reduce disease concerns.