Gardening: Know which annuals don't tolerate transplanting well

Nancy Szerlag
Special to The Detroit News

Some annual flowers struggle as transplants when started indoors early in the season, and so they are  best sown directly into the garden soil. Among these are nasturtiums, nigella, bachelor buttons, larkspur and sunflowers, all of which we plan to grow in the Rochester OPC Stone House Garden this season. 

Our garden will be hosting the second annual Summer Solstice Soiree on June 19 to benefit Meals on Wheels, so we want to make sure it’s in tip-top shape and full of color. Here are some of the plants we will be sowing from seed in the garden this spring to make that happen.  

New Millennium Purple Passion Larkspur
Purple flowers with white centers. 
Tall flower spires on strong stems. Often reblooms in late summer.

Nigella, commonly called Love in a Mist, is a hardy annual that rises to about 2 feet tall and is an early bloomer. The lovely quarter-sized flowers in blue, pink or white  are cushioned by fine fern-like foliage and their seed heads, produced after they mature, are valued for use in dried flower arrangements. Nigella flowers in full bloom also make a nice addition to cut flower arrangements.

An additional sowing of seed about 4 weeks later will produce a fresh flush of flowers from mid-season to fall when spring plantings are popping out. 

While the period of bloom for this annual is brief, about eight weeks,   those successive sowings will keep the color coming all summer if the nights don’t heat up. 

Larkspur (Consolida sp.), long a favorite of mine for its English heritage, is a hardy annual relative of the perennial Delphinium.  When planted as soon as the ground can be worked, they will climb 4 feet or more and bloom and produce blue flowers through the summer if kept deadheaded. Allow seed pods to develop, and if they are in a happy place they will reseed.

In order for larkspur to germinate, the seed must have a cold period. Two weeks stashed in the refrigerator in a zip-seal bag with damp sand will do the job. 

Verbena Bonariensis is a see-through annual plant that produces quarter-sized clusters of purple flowers on thin 3 to 4 feet stems. Prices vary, but a packet of seeds is your best buy and when they’re happy where they live, they reseed like crazy. If that kind of action makes you nuts, pass on them. Personally, I think they’re worth the effort. 

Nasturtiums  and sunflowers are tender annuals that do best when planted after all threat of frost is past, so  we will expect their show to start some time in mid-summer. 

Nancy Szerlag is a master gardener and a Metro Detroit freelance writer. Her column appears Friday’s in Homestyle. To ask her a question go to and click on Ask Nancy. You can also read her previous columns at