The "Fall Follies"
"It's too late to plant. Maybe we should wait until Spring. It's too cold. I have to change the antifreeze in my car. My dog has fleas." Which one of the above statements is accurate when it comes to excuses for not landscaping during the fall season in Alberta? Aside from a little time consumed to change the antifreeze and attend to Fido's discomfort, the Fall is a great time to upgrade, start or at least plan a new landscape. The benefits of Fall landscaping are numerous and will pay great dividends come Spring-time.
Fall is a great time for planting. As temperatures drop and days become shorter, plant metabolism slows down and photosynthesis stops. Plants drop their leaves, sap flows downward and that energy will now be used to create new roots and strengthen existing ones for winter. Trees planted or transplanted during the Fall months stand a better chance of survival than any other time of the year. They have an excellent chance of becoming established in their new environment. There is less likelihood of transplant shock and wilting because of the cooler temperatures and no foliage for it to support. Less watering required to maintain the plant. Fall planted trees can the utilize moisture from melting snow and Spring showers that provide the nourishment they need to survive. Also in the late Fall, nurseries can start digging again as trees harden for winter providing an excellent selection of trees.
Another advantage of Fall landscaping is the construction of retaining walls. When a wall is backfilled and not properly compacted there will be air pockets created between the particles of fill material. The benefit of building the wall in the Fall is that "settling", the compression of air pockets, can take place over the winter and early Spring. If settling does not occur naturally then one good bout melting snow or a Spring downpour can settle uncompacted fill considerably. I've seen an eight foot watermain trench settle two feet overnight from Spring rain. It is much cheaper to top up a settled area in the Spring than having to rip up new landscape to repair the damage caused from settling. It would be prudent to allow a new home to sit unlandscaped over one Winter and Spring to allow for foundation and underground utility settlement.
When possible, I believe it is beneficial to plan a new landscape or renovation in the Fall and winter. If hiring a designer, they will have more time to spend with you during the Winter months. Any important decisions can be made during the off season so that they won't delay work scheduling during the busy season. There can be a lot of information to digest when a customer is first presented with a landscape design. If planned in the Fall they will have all Winter to research different plant varieties and become familiar with all the different components of the landscape design. Then come late Winter - early Spring they can hire a contractor who will be happy to book them in as one of their first customers.
Garden centers sell containerized shrubs. This helps extend the length of time they can be planted as transplant shock is minimal. For someone just learning about plants, they can see first hand at a garden center what plants catch their eye for Fall colour. Amur maples, staghorn sumacs, many of the spirea species, dwarf burning bush, cotoneaster and siberian dogwood are some shrubs that offer brilliant Fall colours. Some perennials that can extend some dynamic colour well past the Summer gardening season are: Perennial mums, Autumn joy sedum, Spiked gayfeather, Blue sheeps fescue and Blue sedum.
A word of caution regarding Fall planting. In areas where there is very little or no snow cover, tender herbaceous perennials and junipers are best left planted until Spring. Perennials that have been planted can be mulched with straw or peat to help prevent moisture loss. I prefer peat moss, as it can be turned into the soil come Spring-time. In Calgary I call upright cedars the "death" plant. Chinook conditions dry them out to such an extent that they are lucky to make it through the Winter. I have heard suggestions of covering them through the Winter. My personal opinion is that I would want to plant something suitable to the environment so I could enjoy its winter colour and not have to look at something resembling a frozen "mummy".
I believe, in Alberta, that we are very lucky to have seasons where we can enjoy the different colourful "personalities" of our available plant species. Although Alberta is known as having a limited growing season, with a good knowledge of horticulture, we can extend our enjoyment of our Summer gardens well past the icy grip of Jack Frost.