Dear Anne, "When I started planting things in my garden, I didn't really look at the group classifications for pruning clematis. Sigh! Now I need to ask." Christina, Burnaby

You should cut early-flowering clematis back right after flowering is finished. It gives them time to make new growth for next year's spring flowers. Hard-prune summer-flowering clematis in late winter, cutting them down a foot or two above the ground. That will give you mid-summer flowers.

Or cut half the summer-bloomers almost to the ground, leaving half for early-summer flowers. The cut half will flower a bit later.

The next year, cut back the vines not cut the year before, and leave the others until the following year, for early and mid-season flowers, for a very long flowering season.

The late-summer/fall flowering clematis can be cut a foot or two above the ground in late winter.

Some gardeners don't consider the different pruning times for clematis, and plant all together on the same trellis, believing they will have ten months of clematis flowers.

What they get is a pruning experience like none other!

Dear Anne,

"Three years ago I planted a four-foot Styrax japonicum tree, adding compost and bonemeal. It bloomed slightly the first season, but has not bloomed since. It is healthy and more than doubled in size but needs a lot of water. It is in partial shade about eight feet from a cedar hedge. Could the cedar roots be invading my tree's root space?

Jonathan, via email

Styrax and cedar both have shallow root systems and need lots of water. But cedar is especially notorious, as its fine mat of greedy roots spreads far and wide.

Styrax trees are slow to mature, and part shade can hold back flowering. The first-year blooms probably developed in response to its previous conditions in the grower's field - probably much sunnier.

But as your styrax grows, it will stretch toward the sun, and with maturity, blooms will increase.

Compost very rich in nitrogen could also promote vegetative growth at the expense of flowering.

Dear Anne,

"I have two vegetable boxes north of a two-storey hedge. They don't get enough sun to grow vegetables. I'm thinking of putting heather in one and another plant in the other. I think having one kind of plant in each box will make them easier to manage.

Mary, via email

Using one type of plant will make your boxes easier to manage. But heather is a sun-lover, and won't do well in shade.

You might try Helleborus orientalis or Helleborus foetidus. Both are evergreen and flower over a long period. H. foetidus has green flowers in January, and H. orientalis offers single or double flowers in pink, purple, white, and yellow in February.

Epimediums have low-growing green leaves in the growing season. They turn brown and hang on the plant till spring. Flowers are usually yellow or white. Epimediums flow gracefully over the sides of containers.

Dwarf rhododendrons might also fit your situation.

Anne Marrison is happy to answer garden questions. Send them to amarrison@ shaw.ca