Frost Hardiness of Annual Flowers

In late April and early May, we are eager to get color in our landscape but we have many annual flowers in our greenhouses and a few outdoors ready for sale that should not be put out in the ground immediately.
However, perennials in the yard are ready to be planted.
Also potted flowering bulbs of daffodils and hyacinth can be put in a garden location now. Fertilize while the leaves are green and they will bloom again next spring.
Annual pansies, violas, snapdragon and sweet alyssum (in the feature photo) can all be planted early. The flowers might get a bit singed by frost but won’t kill the plants. You can always put a light sheet over them if frost threatens.
The chart pictured below gives you the general hardiness guidelines for some common annual flowers. Note, this refers to annual dianthus and coreopsis, not the perennial species of these which are hardier.
This chart was adapted from: Walter Reeves Frost Hardiness Chart
Tips for the Winter
Winter is a great time for gardeners to take stock, tidy up, protect plants and plan ahead. And have a look at our seasonal decorating ideas!
Winter Articles