Frequently Asked Questions

Q. How do I care for three small Acer palmatum seedlings that are about one-week old?

A. If you have these seedlings indoors, put them in 10 cm (4″) pots for now, using a potting mix that has some nutrients. Give them plenty of light each day, but not direct sunlight, and water them as needed. Start around the beginning of May, harden them off. Do that by taking them outside for longer and longer periods each day, exposing the plant to outdoor conditions. After about a week, you should be able to leave them permanently outside. Pick a reasonably sheltered location — give them morning sun, but some protection from the hot afternoon sun, especially important for young trees. Red-leaved cultivars need more sun than green cultivars in order to develop good colour.

Fertilize with a high nitrogen fertilizer — follow the instructions on the container, and do not over-fertilize. Water as needed, preferably early in the day.

They can stay in a pot until they are three to four years old, but will need to be potted into a 15 cm (1 gallon) and maybe eventually 22 cm (2 gallon) container, depending on how quickly they grow and how tall they become. When the pot seems full of fine roots, it is time to go to a larger pot.

Japanese maples don’t like temperatures much below -10 C (14 F) so, for the winter, either sink the whole pot into the ground, or move the pot into an unheated shed after the tree is dormant.

It will be interesting to see what form and colour your seedlings develop as they mature. Each of these seedlings is a genetic individual, so will have inherited characteristics from both parents. It is a good idea to keep as many seedlings as you have space — it takes quite a bit of time for the characteristics to emerge — and then you can keep the prettiest ones; the ones with the best form and colour, for yourself and give the others away.

When you finally pick the location you are going to plant them, they prefer a nice loamy soil with high organic content and even moisture. Don’t plant them in a site with too much exposure to the sun or drying winds.

MG

Q. Are the ingredients in mulch safe for children and pets?

A. We asked this question to one of our members, Gro-Bark (Ontario), which produces many varieties of mulch. The response is below for the products Gro-Bark produces.

We are unable to speak for all mulch producers, but the colourant Gro-Bark uses is an ironoxide colourant that is non-toxic to plants, animals and humans. If you visit the company website at www.gro-bark.com you will access a brochure on Colorbotics which is our colourant supplier. The direct link is www.gro-bark.com/brochures/gro-bark-enhance-coloured-mulches.pdf.

Kerri Stevenson,
Gro-Bark (Ontario)

Q. I have some birch trees that are troubled by an insect.
What do I do now that we are not able to use pesticides in Ontario? Any suggestions?

A. Having researched the problems with birches and coming to the conclusion that you may have a European Birch ‘Youngii” or Betula pendula “Youngii” I discovered that although this ornamental tree is quite beautiful with lovely yellow fall colour, it a tree that requires more maintenance in the form of spraying than other trees in the birch family.

The tree has a history of being succeptible to the Bronze Birch Borer which bores its way into the sapwood of the tree, lays eggs in the trunk or branches in August and goes through four instars (stages) over a period of two years and then exits leaving a “D” shaped hole in a six week period beginning in June and ending in July. The tree will have swollen areas of the trunk and leaves will be chloric or yellow and the foliage in the upper crown of the tree.

I would have to say that only a certified arborist could make the final diagnosis of your tree. Having done that, the arborist would then know what treatment could be made to your tree. The arborist would have a license for treating your tree.

Find a certified arborist near you on the Landscape Ontario Find a Company page here. I hope this answer helps you.

Valerie Liney
Lake Simcoe South Master Gardener

A. Spaghetti squash requires 100 days from sowing the seed to harvest. It is easy to grow in your area. Plant it in rich soil, in a sunny site, and give it plenty of moisture. Your harvested squash will keep several months in cool storage, so you’ll enjoy them right through the winter.

Q. Can you recommend a small tree (max. 10 feet), east facing, that can withstand wind?

We have gone through two weeping pussy willows in the last five years. The trees flowered and started to grow leaves, then died shortly after. Unfortunately, the last few years, we’ve had warm weather, then cold, then warm, etc., and that is not helping. Burlington, Ont.

A. A 10-foot maximum means you are really looking for a shrub. The suggestions below depend on what is available at your local nursery. Since you had a deciduous tree there to start with, the plants listed below are all deciduous choices.

• Amelanchier sp. or serviceberry
  Most are taller than you want but there are cultivars that are only about 3-3.5 m tall. These bloom early in the spring, have edible berries (much loved by birds) in early July, and bright red fall colour. They are very hardy.
• Sambucus canadensis — elder
  About 3 m tall and wide. It has fragrant and showy white blossoms in June and dark purple berries (good for making wine and jam if you get to them before the birds) late in the summer. There is a cultivar called ‘Aurea’ with yellow overtones in the foliage. I have seen a beautiful cultivar with pink blossoms and burgundy foliage that is very attractive.
• Magnolia ‘Susan’
  About 2.5 m tall, reddish-purple flowers, green foliage, bronze fall colour.

And here are a couple of hardy smallish trees:

• Acer ginnala
  Also called amur maple or flame maple, 6-7m tall, wonderful red fall colour.
• Prunus virginiana (Schubert choke cherry)
  About 5.5 m all white flower, red berries, green to maroon foliage, red fall colour.

I am not sure what you mean by weeping pussy willow. Pussy willows (Salix discolor) are upright shrubs and are very hardy. They do like moist, almost wet, soil and lots of sun. Perhaps it was too dry for them in this location. If this was a graft of pussy willow branches onto some other rootstock, maybe the rootstock wasn’t hardy enough or did not deliver enough moisture to the grafted branches. It is a concern that the willow did not survive in this location. It may have been affected by other plants growing in the area.

MG

Q. Can you suggest a shrub to put alongside a Diablo ninebark?
It would be facing east and the soil would be normal to dry. I was thinking of Pinky Winky Hydrangea or smokebush (but that’s kind of big). Markham, Ont.

A. A Diablo ninebark looks nice when flanked by two dwarf Japanese barberry cultivars called Golden Nugget. The mounding form fits beautiful nestled beside the taller cascading ninebark. The contrast in colour and texture is quite dramatic. They love the morning sun and are drought tolerant.

Linda Hugli
Master Gardener

Q. Can you suggest a vine that will grow on our pergola and will not attract bees?

A. I would recommend a clematis called ‘Prairie Traveller’s Joy.’ It is very hardy, unusually vigourous, and produces small white flowers in mid- to late-summer (unlike many clematis cultivars) that do not seem to attract pollinators. It still sports the interesting seedheads.

Several years ago, I planted one on each side of both our arbour and a seating nook. By the end of June, I found myself cutting the vines back just so that we could walk through the arbour. The nook is a wonderful shady respite when my gardening chores have exhausted me.

Linda Hugli
Master Gardeners of Ontario

Q. I’m looking for suggestions for deciduous, flowering, fragrant shrubs for a shaded and moist area in zone 5.

A. There are a few fragrant deciduous shrubs to try in a shady Zone 5 site.

A few suggestions:
Daphne ‘Carol Mackie’ — beautiful variegated foliage
Azaleas – ‘Northern lights’ series — Mandarin and Orchid are best
Philadephus (Mock Orange) — citrus scent, white spring blooms
Summersweet (Clethra) — will tolerate even full shade, native

Linda Hugli
Master Gardener

Q. Can you please tell me if most vines hold their leaves all winter? We have a trellis between us and our neighbour and would like some year-round privacy. Looking for any suggestions on a nice flowering vine that keeps it leaves all year?

A. Unfortunately, there are only a few vines that keep their leaves all winter, and they do not have any flowers. One suggestion might be to plant an evergreen in front of your trellis, which would give you privacy year-round. You could then grow one of the many beautiful flowering vines behind it.

You did not mention whether the area receives a great deal of sunlight, or if it is in the shade. This would affect your decision on the type of vine you would like to plant. If there is not enough room for an evergreen, or if you really do not want one, the only vine that would remain evergreen would be English Ivy Hedera helix. The plants are very vigorous, can quickly spread to form a dense patch, or form aerial roots to climb up vertical surfaces. Cold, dry winds or full sun may cause scorching in the winter, so your site should be sheltered. If the plants get out-of-control, they can be clipped back at any time. Although you will not get flowers on the ivy, there are many varieties with variegated leaves, such as “Little Diamond,” which is grey-green in colour with a creamy white edge. “Thorndale” has small, leathery, dark green leaves with prominent white veins, and a bronzy-red winter colour, and “Glacier” has small, dark green leaves with creamy-yellow margins. Although you would not get the flowers, you could have very attractive foliage.

June Streadwick
Zone 5 director
Master Gardeners of Ontario