Weather Words: Phenology

I can still hear my grandmother say, “We can’t plant our tomatoes until after Easter.” I always wondered what Easter had to do with tomatoes, but growing up in Louisiana, our growing season did, in fact, align with when Easter typically occurred.

Tomatoes are one of those vegetable plants that don’t do well in freezing conditions, and for northern Louisiana, we were typically safe from freezes after Easter.

Phenology is the study of cyclical, seasonal natural events, like when plants bloom or when birds migrate. But it goes beyond that. It’s knowing when to plant our gardens and harvest crops, based on climate and weather within that region. It’s the breeding patterns of animals, the emergence of insects and even when our waterways become ice-free in the spring.

The National Phenology Network is an excellent resource for not only learning about the latest research and studies that are being conducted in the phenology world, but also when to plant, when to expect the last freeze and so on. So maybe you’re in more of a “Tomatoes can’t be planted until after Memorial Day” region of the U.S.

Jennifer Gray is a weather and climate writer for weather.com. She has been covering some of the world's biggest weather and climate stories for the last two decades.