L'automne arrive dans le jardin

Le premier gel qui annonce l'approche de l'hiver nous rappelle aussi que c'est le temps de "mettre au lit" la saison de croissance. 

Deborah Peck nous offre des renseignements et des conseils utiles pour garder nos plantes en santé pour l'an prochain.

Fall in the Garden
Time to Wrap-Up for Winter

Deborah Peck
Plant Science / Greenhouses
UNB Department of Biology, Fredericton

October 1999


hen the first killing frost announces the coming of winter, it's time for gardeners to think of the tasks that are required to "wrap-up" the growing season.

Gardening Supplies
(photo: Deborah Peck)

In the vegetable garden there might be pumpkins to harvest, carrots to dig, and green but firm "winter-keeper" tomatoes to pull from the vines. In the annual beds there could be seeds to gather and tuberous begonias to take indoors. Composters can empty their bins or turn their piles.
Growers of grapes can enjoy their harvest. Strawberry enthusiasts can order the straw that they will cover their patch with in the late weeks of November. Like squirrels gathering nuts for their burrows or like big game animals fattening themselves against New Brunswick’s long months of frigid cold, gardeners spend weeks in the fall preparing their landscapes for the challenging weather to come.


Protect those plants!
(photo: Deborah Peck)


The following are some tips that gardeners can use to prepare for the oncoming cold weather season.

One of the most pressing fall tasks for those who grow Dahlias or Gladioli is to rescue these "tender" plants before they are damaged by excessive freezing temperatures. Gladioli corms and Dahlia tubers can be dug after the above ground portion of the plant has been touched by a very light frost. Gladioli leaves and any remaining flower stalks should be cut back to within six inches of the corms before they are lifted and moved indoors to a cool, dry spot, to dry for several weeks. Then, the corms can be stored in mesh onion bags, paper bags or in open-sided plastic crates. Dahlia stems should also be cut back to within six inches of the ground before the plant's tubers are carefully dug with a shovel or spade. The tubers should be turned upside down and stored for a few weeks indoors in a well ventilated area to allow moisture to drain from the stems. They can then be kept upright, in a box filled with barely moistened sand, peat or straw.

Just after Gladiolis and Dahlias are lifted from the garden, spring flowering bulbs should be put in place. Tulips and daffodils, hyacinth and crocus, muscari and scilla should all be planted early enough in the fall for them to develop a root system before the ground freezes. As a general rule, bulbs should be planted at a depth that's equal to three times their height. It's beneficial to drop about a tablespoon of bone meal into each planting hole before putting a bulb in place (bone meal is a good source of phosphorus that will encourage better bloom). Then the planting site should be watered well and mulched with fallen leaves. If squirrels have damaged your bulbs in the past, try planting some Fritillaria this year. Commonly known as Crown Imperials, these bulbous plants have a strong skunky smell that repels squirrels and other pests. Their spectacular, long-lasting flowers are an added bonus!

Garlic should also be planted in the fall. Since grocery store varieties are not recommended for home gardens (they are sometimes treated with a sprout inhibitor), choose plump, fleshy garlic bulbs from a garden centre. Pull away individual cloves and plant them, pointed end up, in a sunny location that has well drained soil. Mark the planting spot appropriately so that the garlic will not be disturbed while you're cultivating the garden next spring.

Shovel & Seeds
(photo: Deborah Peck)

Gardeners who have a collection of tender hybrid tea roses should be planning to protect their plants for the winter in one way or another. These types of roses can be dug from their growing spot after their foliage has been killed by frost (but before the ground freezes completely) and then buried in a hole that's at least two feet deep in a very well drained spot in the garden. They can be dug out again next spring for replanting; the plants can be left in their current growing place, mounded with compost (to a depth of at least one foot), and then completely covered with dry leaves or straw mulch.

Many shrubs and trees also need some type of winter protection. Specimens that are close to buildings, where they are apt to be crushed by snow falling from the roof, should be covered with a solid frame that will deflect snow and ice. Evergreens that have been planted in sites that are exposed to high winds and blowing snow should be wrapped with burlap. Rhododendrons, however, should simply be surrounded by burlap that is held away from their foliage by stakes pounded into the ground around the perimeter of the plant (they suffer from being wrapped too tightly). If mice have damaged your shrubs and trees in the past, consider investing in plastic or wire mesh "stem wraps" that are designed to keep mice from chewing on bark.

Hardy herbaceous perennial plants usually need little or no winter protection. Some gardeners prefer to cut the stems of perennials back to ground level in the fall and then cover the plants with a mulch of leaves or evergreen boughs. Other gardeners prefer to leave the plants' dead foliage in place to act as a snow trap.

Finally, gardeners should consider taking the time to write a journal of this year's successes and failures. It's amazing how quickly we forget about where we planted the hollyhocks or the foxglove, what variety of carrots, cucumbers, marigolds or petunias we had the greatest luck growing, what type of tomatoes grew the fattest or the tallest and the names of those daylilies we got on sale in July. A record of your planting achievements will be a great resource when the seed catalogues start arriving next January!