Spring Planting: Annual Plants
Check Your Frost Date Know Your Microclimate and Harden Off Annuals Before Planting
Apr 25, 2006
Annual flowers grown for transplanting are sold in cellpacks or small individual pots. Most of these should not be planted in the garden until after the last spring frost. (There are some exceptions such as violas and pansies which are sold as special cool season annuals.)
Check Frost Date
Use the following maps to check your average spring (and fall) frost dates. Keep in mind that this is an average so some years the last spring frost will be earlier and some years it will be later.
Microclimate Matters
Your microclimate can also affect the frost patterns in your garden, so your specific frost date may be a week or ten days earlier or later than the average for your area. This is something an experienced gardening neighbor may be able to help you with. It is worth noting the last frost date in your garden and recording it in your garden journal as well. Over the years you will begin to see your garden's average compared to the published date.
Hardening Off Helps
If your annuals are straight out of the greenhouse and very tender, you may need to condition them or acclimate them to being outdoors in real sun and wind conditions before you plant them in the garden. This process is also called hardening off. If you don't take the time to do this, they will be stressed when you transplant them into the ground and they may be stunted as a result.
To harden off your newly purchased plants, place them in a sheltered spot with morning-only sun and protected from the wind. Water as needed to keep the soil slightly damp like a wrung out sponge. Cover them or bring them inside at night if frost threatens. After about a week, or longer if the weather still has not settled, plant them in the garden. Watch your weather forecasts and continue to protect them from frost as needed.
Happy Spring!
This is part of a series on when to plant in the spring.
