Dear Anne,
“In 1991 we moved into our house (built in 1935) and with it came a rose that is looking quite pitiful now. I love its fragrant flowers but I am afraid to prune it so I don’t kill it and therefore lose it forever. What can I do to improve its growth?â€
Jadzia, North Burnaby
Old roses have super-strong roots and strong, new growth is quick to emerge after pruning.
But pruning isn’t a good idea right now as we head into frost season. If we get an exceptionally cold spell this winter, the new growth could die back.
In early spring, just as the buds start to swell, you could remove any dead, diseased, spindly, or damaged rose stems, then begin pruning the good, strong stems.
If your rose is a climber, cut back enough of the main stems to fit into the space you have for it, then prune the side shoots back by one third.
If it’s a bush rose, cut the strong stems back by two thirds. If that seems too drastic, just do one third. By the time you’ve also fertilized your rose, you will be surprised at how quickly it grows back.
Usually the larger pruning prompts the rose to grow faster and further, because the energy in the roots needs to be expressed above ground.
Roses thrive on extra water through our long, hot summers. It helps them if you mulch them so they retain moisture. Use compost or bark mulch, or even straw or grass clippings, if the rose isn’t in a regular garden bed.
Compost or manure is good nutrition for roses. Garden centres sell many kinds of fertilizer especially for roses.
Old roses are prone to a fungal infection that causes black spots on the leaves. It looks horrible, but doesn’t kill roses.
Disposing of black spot leaves reduces infection next year. Fungicide is still sprayed by some, others just ignore black spot.
Dear Anne,
“Do you know why a beautiful 15-year-old camellia in a large planter would suddenly die after being dripped on by a new deck painted with latex, oil-based, and fibreglass products?â€
Carlyne Haynes, Vancouver
Your camellia roots probably got burned or poisoned by the products that dripped on it. Repotting it immediately would have been a daunting prospect with a shrub that old, but if the roots were washed and repotted in all new soil, it might have lived.
If a similar accident ever happens again to a big, old potted plant, try putting it under an outside tap on a slow drip for a few days.
Another thought: your plant might re-shoot from the roots if you leave it out during winter rains.
Is it possible that previously your camellia wasn’t under any deck, but was placed under a new deck while the deck was still being coated?
A position under a deck can be a very dry spot – and camellias need a lot of water.