Well, it depends. But it really does depend on where you are, zone-wise. All Zones can plant spring-flowering bulbs and dormant perennial plants up until the soil freezes solid. If you do this, please water well until ground freezes. Indoors, start seeds of cactus, coleus and impatiens, and parsley, chives, oregano and spearmint, for indoor growing during the winter and spring.
All squash varieties are tender, needing to be planted after all frost is past in spring.
Squash grows through the summer, blooming and producing fruits. They are consumed right away, raw or cooked. Examples of summer squash are zucchini and crookneck. They are picked just before frost hits them in late fall. Winter squash will store well for several months in a cool place.