|What plants can be started as soon as the ground can be worked in the spring. I am also interested in plants that can be sown in the fall as well. Thank you. My zone is 6.|
|There are lots of cool season annuals and you can sow seeds as soon as the ground is workable:
Bachelor's Buttons, Cornflower (Centaurea cyanus) A cottage garden plant, Bachelor's Buttons give its best display in cool seasons, so if you started some in the spring, watch as they perk up again this fall.
Calendula: Calendula looks like a fall flower, with its rich golden and rust colors. They might even withstand a light frost, if they're established. Many calendula will self-seed and treat you to a spring bloom as well.
Diascia though relatively new in gardens, became popular quickly. The tiny, profuse trailing blossoms make it perfect for containers. Diascia is generally grown from cuttings, which can make it an expensive annual. But you may be able to oover winteryours indoors or take your own cuttings.
Lobelia will give out on you during the summer. But given cool temperatures, it will bloom with pprofusion If you planted yours in the spring, once the flowers start to slow down, cut it back a half and allow it to regrow and rebloom.
Nasturtium will bloom throughout summer, well into fall. They are rejuvenated by the cooler air. Even their crisp fall colors advertise that they belong in the fall garden. Nasturtiums don't transplant well and you may be better off direct seeding. Keep them well watered in the heat of summer.
Nierembergia 'Mont Blanc' rescued nierembergia from obsolescence Nierembergia is hardy to Zone 7 and can even be over wintered indoors, but you might not bother because it is fairly easy to grow from seed. 'Mont Blanc' won the AAl America Selection award, but the blue flowered varieties are getting the attention now.
Petunia: Gardeners think of petunias as a bedding mainstay. Petunias actually do their best blooming in cool temperatures and there are so many to choose from. The Wave series has become especially popular and if you, like me, don't like deadheading, Wave petunias are for you. The tiny calibrachoa petunia make a nice textural accent in containers.
Snapdragons offer you color and a bit of height, depending on the variety. There are also new trailing snapdragons that work wonderfully in containers. Look for the Luminaire? series.
And, of course, Violas and pansies will bloom for weeks. Deadheading will keep them setting new buds. Look for some of the newer varieties that can handle a slight freeze.