We get a lot of emails at Frankie Flowers asking about when is it safe to plant outdoors, but it all depends on the type of plant. Trees and Shrubs can be usually be planted when the ground has thawed. Perennials are best planted in the first year after the risk of heavy frost has passed, and they will be fine each year after that, as perennials overwinter and grow back each spring.
Annuals and vegetables are a different story. Annuals cannot survive the winter, so they only live for one growing season. There are a few perennial vegetables, but most are annuals too, meaning they won't come back year after year. Some annuals and vegetables can take heavy frost, some can take light frost, and some will die if even a light frost touches their tender leaves. How do you know which is which? We have put together a list of common annual flowers and vegetables, and when they can be planted outdoors.
You can check your last frost date here.
Can be planted 4-6 weeks before last frost date
Vegetables: Asparagus, Collards, Endive, Kale, Kohlrabi, Lettuce, Onion, Parsley, Pea, Rhubarb, Spinach, Turnip
Flowers (Annuals): Pansy, Primrose/Primula, Violas, Ornamental Kale, Ornamental Cabbage, Hardy Chrysanthemum, Cordyline, Dracaena (spikes), Marguerite Daisy, Nemesia, Osteospermum, Snapdragon
Bulbs: Daffodil/Narcissus, Hyacinth, Crocus, Allium, Tulips
Can take a bit of light frost, can be planted 2-3 weeks before last frost date
Vegetables: Beet, Broccoli, Brussel Sprouts, Cabbage, Carrot, Cauliflower, Celeriac, Celery, Chard, Radish, Parsnip
Flowers (Annuals): Calendula, Stock, Sweet Pea, Dusty Miller, Geraniums, Petunia, Victoria Sage, Verbena, Cosmos, Gazania, Calibrachoa
Tender/ Frost Intolerant
Plant after last frost date, protect if a late frost hits after planting
Vegetables: Sweet corn, Tomatoes, Peppers, Cucumber, Okra, Eggplant, Summer and Winter Squash, Watermelon, Pumpkin
Flowers (Annuals): Nicotiana, Statice, Lobelia (annual), impatiens, Rock Moss/Portulaca, Marigold, Zinnia, Annual Phlox, Begonia, Ageratum, Celosia, Coleus, Potato Vine
Bulbs: Gladiolas, Dahlia, Calla Lilies