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Deadheading best while dallying in garden

A daily walkabout in the garden is one of the most relaxing habits a person can get into - it's also incredibly useful if one takes a pair of pruners along to do deadheading along the way.

A daily walkabout in the garden is one of the most relaxing habits a person can get into - it's also incredibly useful if one takes a pair of pruners along to do deadheading along the way.

Many perennials will bloom again if the old flowers are cut off as soon as they begin withering.

These include lupins, valerian, verbena bonariensis, cranesbills, campanulas and geraniums.

Re-blooming is the response that almost all the daisy-type flowers make to deadheading. This includes zinnias, helenium, echinacea (Coneflowers) and Shasta daisies.

Most should be cut back to the next lower bud. Or if that isn't visible, cut to just above the next lower leaf.

Once a stem's main flower is gone, the energy it would have used becomes available to dormant buds lower on the stem so they quickly develop and bloom.

That's why some detail-oriented gardeners prune out the first bloom on plants such as phlox or snapdragons.

They feel that this triggers dormant buds lower down so that the sideshoots bloom earlier and in larger quantities than they otherwise would.

Annuals need frequent deadheading, otherwise they stop blooming as soon as they begin forming seed.

Sweet peas, for instance, are notorious for ceasing to bloom unless picked every day or two.

Other plants that are grown more for foliage than flowers are often deadheaded to liberate more energy for the development of healthy, luxuriant leaves. This applies especially to some of the artemesias and to santolinas.

But some of the taller cranesbills also get very leggy and gangly after flowering and really benefit by flower-heads and foliage being sheared close to the ground so that a mound of vibrant, fresh leaves develops.

This all-over haircut also works well with Catmint (nepeta), Ladies Mantle (alchemilla) and other plants that grow low and/or produce zillions of flowers that would be too fiddly to deadhead.

Flowers that open over a long period within clusters invite difficult decisions.

Lychnis coronaria and astrantia both have ripe seedpods in their flower clusters while later-opening flowers in the same cluster are still blooming. Both self-sow prodigiously. Lychnis pulls up easily, but astrantia has a taproot.

Spires are similar. Foxgloves produce almostripe seedpods at the base of the flower stalk while more blooms continue to open at the top. Efficient gardeners usually cut sooner rather than later.

There are a lot of different benefits to deadheading. Preventing plants from forming seed can save you a lot of work next spring - and some beautiful, valuable species have tap-rooted seedlings as numerous as dandelions and just as diabolical to remove.

Hellebores and bronzeleaf fennel are two where gardeners need to do selfprotective dead-heading.

The hellebore seedheads especially can be quite beautiful - but when the green begins to fade, it's immediately time to decapitate them.

Other plants, like astilbe and the Sea Hollies (Eryngium species) aren't major self-seeders and really enhance the look of garden beds when they're left standing through winter.

Some of these are as pretty as flowers when rimmed with frost on winter mornings.

Then there are the seedheads that provide food for birds in fall. Rudbeckia, sunflowers, zinnias, cosmos and all the thistle family produce seeds that birds love to feed on.

Anne Marrison is happy to answer any gardening questions you may have. Send queries to her at amarrison@ shaw.ca.