Say uncle

Some gardeners are smart enough to know when to say uncle. Hydrangea never blooms? Banish it to the compost. Globe cedar lost its globe shape? Repent, replant and move on. Husband allergic to roses? D-I-V-O-R-C-E.

This kind of tough love in the garden can be learned if you rub shoulders with the right people.

I've been on the hens and chicken circuit lately and I've recruited some expert help from the Royal Botanical Gardens when I'm feeling wobbly. Gardener Bob May is a precision pruner. We've been double-teaming pruning demonstrations recently. When I get a question about rescuing some rickety shrub I recommend everything short of last rights. Bob's response is hack and slash. Hack down the weigela and spirea, cut the butterfly bush down to the size of corn nibblets, climbing roses can be reduced to three to five good canes, wisteria needs a serious slashing several times a year.

And really, does your Alberta spruce owe you anything after 35 years in the garden? Still people are astounded when their plants want to die with dignity, they just don't want to give up. A corkscrew hazel has really delivered the goods if it's graced the garden for 30 years. If it dies, don't cut it down, use its lovely twisting branches as the scaffold for a climbing vine like a clematis.

A befuddled gardener asked if she should pay an extra 200 bucks to have all the stump and roots of her dead mountain ash tree removed. Save the money, and leave about a two-foot stump, which has been cut off level. Then use that as a perfect platform for a big container of flowers. Imagine heuchera 'Lime Rickey' with lady's mantle and the new periwinkle called 'Illumination'. It would make a luminous tableau of apple green.

On duty at the RBG Ask the Expert booth at the gargantuan garden show in Toronto, Canada Blooms (www.rbg.ca), people lined up six deep to get help. One woman asked if she should prune her newly planted convoluted hazel. Well the hazel is really called "contorted" the question perhaps was convoluted. For gosh sakes leave the poor hazel alone, they are slow growing to begin with, so why lop off its branches because someone told you to.

Had the same question about the loveliest of shrubs called doublefile viburnum. Just planted, still knee-high to a grasshopper, and here's a trigger-happy gardener ready to saw off a few feet of it for no good reason. If you put the doublefile viburnum in the right place, you should never have to prune it. It gets wider and more majestic every year and makes every inch of the garden space it occupies a prettier place.

For practical advice, delivered with a sly sense of humour, gardeners should flock to talks given by John Valleau of Heritage Perennials (www.perennials.com). I sat in on one at Canada Blooms, and my notebook was filled in 15 minutes.

Some nuggets from Valleau. The perennial coreposis 'Zagreb' is often a better performer than the much-touted coreopsis 'Moonbeam'. I agree, it's as reliable as Derek Jeter at shortstop.

There is no magic pill to getting rid of weeds. Right on John, sometimes you just have to hand pull and pull and pull.

Got a slugfest going on in the hosta patch? Valleau says mulch with pine needles. The soft- bellied slugs hate crawling over the prickly pine needles.

Stumped over how to combine colour in the garden? Valleau says borrow the gimmick from sports jerseys and use contrasting colours. "Purple and chartreuse always work. Use lady's mantle and a dark leaved barberry or think of alliums with laburnums," he says. All curious gardeners should hear Valleau speak. His itinerary is available at www.perennials.com.

So don't be afraid to hack and slash, bury the dead, and go for contrast not conformity in the garden.