Put your garden to bed in the fall

Now's the time to tend to the matters that need tending in the garden. How to protect your plants and get a jump on spring.

Credit: Terry Guscott / Alison Miksch

Protect your plants and get a jump on spring.

Whether it’s pruning, mulching, dividing perennials, or renovating, fall is the perfect season to get your garden act together and give yourself a head start on next spring. It is amazing what rewards will come your way if you spend a little extra time in your yard now. So don’t put away your garden gloves or rinse off your tools just yet – there is still work to be done.

Cut Foliage
1. Cut foliage and stems back to crown
2. Pack insulating material around trunk to a thickness of 20-30 cm.
Cover crown
3. Continue process until the top of the crown is covered.
wrap material
4. Wrap insulating material with a layer of burlap and secure with string.
cap with plastic
5. Place a plastic cap over the top to keep water from settling in the crown. Secure with string.

temporary mulch
For most gardeners, fall is the time of year for a well-deserved rest – to take a breath and to rest weary backs after a long season of pulling weeds. For those in the know, however, this is the time to get busy and tend to the matters that need tending.

1. Placing a temporary mulch of fir boughs around a tender plant provides protection from the cold while still allowing for air circulation around the crown.
insulate with straw
2. Straw is a good insulator — remove it in spring.
scatter straw
3. Loosely scatter straw around your tender perennials to offer added winter protection.
use fallen leaves as mulch
4. Fallen leaves placed around plants and over bare earth are a great source of insulation and suppress weeds.

But don’t get me wrong; not all of the tasks will be drudgery. In addition to the requisite weeding and pruning, you can also enjoy some fun. Consider creating some unusual winter containers, planting beds with winter annuals and spring bulbs, and combing garden centres for bargains.

To put your garden to bed effectively, you will need to prepare a plan. Look around your yard to identify what tasks need to be done and which problems need to be remedied before the next season. Be critical and make notes on everything: trees, shrubs and perennials that need to be pruned, divided or moved; tender plants that need to be brought indoors for the winter; and problem spots that need renovating. By creating a “to do” list, you can systematically move through your garden, tackling the most important jobs first. This also allows you to schedule your time around the weather. Fall weather in British Columbia can be quite variable, but there should be enough fair-weather days in October for you to get everything done, so save the rainy days for bargain hunting.

The first task at hand is general garden tidying. There are two schools of thought when it comes to fall cleanup. You either cut down everything dead or withering in the fall, or you leave it until spring. Each approach has its advantages and disadvantages. By ridding the garden of debris in the form of dead or dying stems and leaves, you are creating a very neat and tidy garden for winter. You are also removing potential sources of plant pathogens, which is especially important if you grow roses and tomatoes.

Having too clean a garden, however, can come at a cost. By removing all debris, you open up your garden to a number of problems. Not only do you end up exposing the plant’s tender crown to the elements, but you also expose the soil surface to wind, rain and possible erosion. This can prove to be a particular problem in windier locations of the province, such as the Central Fraser Valley.

You will need to decide on which school of thought to follow. The sight of spent perennials and grasses covered in dew on a misty fall morning can be breathtaking, and to forsake such sights in the name of tidiness is surely a mistake. Perhaps the best approach is to strike a balance between the two, leaving some plant material that offers winter interest, such as grasses and perennials with unusual stems and seed-heads, and removing anything that is unsightly. If a plant requires some protection after you remove the debris, then you can place a mulch over its crown to protect it.

Mulching is extremely important, as it provides innumerable benefits to your garden. By placing mulch on your garden or around tender plants, you are effectively placing a blanket over your garden, protecting it from the harmful effects of winter. While top growth of many trees, shrubs and herbaceous plants can withstand low temperatures, roots can be extremely sensitive to cold. Mulch acts as insulation for the root zone.

Mulch can also suppress weed growth, which is especially important for gardens in the Lower Mainland and Vancouver Island where weeds grow year round. Weeds are effectively smothered, preventing them from maturing and setting seed. Mulch is also great for reducing soil erosion. By covering bare earth with mulch, you can greatly lessen the detrimental effects of wind and rain. Some mulch, such as shredded leaf mould (composted tree leaves), will return organic matter to the soil upon decay. This type of organic mulch can be left on the garden in spring.

Other types of mulch are more temporary and require removal in the spring. Good examples of these would be clean straw or conifer boughs placed around the crowns of tender plants. Straw and boughs offer the same sort of protection as do the previous two mulches, but they return no organic matter to the soil, offer little weed suppression, and are also a little more unsightly. The benefit to using these mulches lies in the fact that they offer insulation from cold, while still allowing aeration around the crowns, preventing some rots that can occur during the wet winter season. All mulches should be removed from the crown as soon as a plant begins to sprout in early spring, or after the danger of frost is past. Leaf mould can be redistributed around the garden. For gardeners in colder areas of the province, nature supplies an abundance of snow, one of the finest mulches possible – providing natural insulation for the plants lying dormant beneath.

Another form of mulch, not appropriate for garden beds but perfect for vegetable gardens or large areas of exposed soil, is a cover crop or “living” mulch, such as fall rye. After the vegetable patch has been cleared for the winter, sow fall rye over the area. Upon germinating, the bare earth will be replaced by a vigorous crop of rye. The rye will continue to grow through the winter, preventing erosion and weed growth. In spring, when you till the rye into the earth, it will act as a green manure, benefiting the soil with the addition of organic matter.

Think of wrapping as vertical mulching – a means of protecting a tender plant from the
elements by covering its stem or trunk with a barrier against cold, winter wet or both.
Gardeners in the colder areas of our province may already be familiar with wrapping conifers to combat the effects of low temperature and snow load. On the coast, the need for wrapping is growing as tender plants such as bananas, palms and tree ferns become increasingly popular.

A variety of materials can be used to wrap plants. For bananas and tree ferns, the most common items for insulation are straw or leaves that do not easily decompose (preferably beech or oak). These materials are loosely packed and encased around trunks or stems using burlap, snow fencing or plastic/poly. The best casing materials are the first two, as they will allow air circulation around the plant, limiting the risk of rot. Secure the casing material with rope or string and cut out a piece of plastic to create a cap over the top to prevent water from sitting in the crown. This may be an unsightly method of overwintering tender plants, but it’s a necessary one if you want to grow exotics.

Storing Tender Plants
Growing tender plants and exotics certainly comes with a few drawbacks, including their expense and the special conditions they require to ensure survival through the winter. Even if you do not have a greenhouse, it is still possible to save these plants for use next year. Some plants, such as echevaria and agaves can be grown as houseplants. Rhizomatous or tuberous plants, such as begonia, canna, caladium, dahlia or colocasia, can be dug, cleaned and stored in lightly moistened peat moss in a cool basement or frost-free garage. Other plants, such as tibouchina, fuchsia standards and geraniums, can be stored in a cool, moderately lit environment. They may end up looking worse for wear by spring, but will return to perfect health once given proper growing conditions, pruning and fertilizer. If you have a little extra space in your basement, garage or covered patio, it is worth a try to save these plants from year to year. You spent good money on these items, so it would be a shame to throw them onto the compost heap. Just remember to dig and store these plants before the first frost in your region.

Garden Renovations
Fall is the perfect season to tackle garden renovations, while the look of your garden during the summer is still fresh in your mind. Moving misplaced plants and removing those that are unwanted or overgrown are ideal jobs for this season. The impact of these renovations will be less noticeable, and you will reap the full benefits come spring. Plants moved, divided or planted in the fall show less signs of transplant shock, as the waning temperatures at this time of year will allow these plants to become accustomed to their new homes.

The Shopping Spree
If you have a little extra cash in your garden budget, fall is the season to shop. It is a notoriously slow time for garden centres and bargains abound. While shopping for spring bulbs and fall bedding plants, take a look around at other merchandise. It is common for stores to deeply discount out-of-season items. Buy things you are going to need next spring, such as containers and pots. Nurseries don’t like to keep inventory over the winter, especially when it comes to perennials, trees and shrubs. Plants may not look at their peak, but once planted they will be better than ever next summer. If you notice any gaps in your garden that need to be filled, now is the time to go out and take advantage of some great prices.

The Finish Line
Once you have accomplished these major tasks, then you can finish off with a few miscellaneous jobs. Remember to bring in clay pots that are not winter-proof and store them in a frost-free environment. Gather up all the stakes that were holding up your perennials. Collect all your tools and give them a good cleaning, removing all debris and drying them before storage. Oil any pruners, loppers or saws that require it. Winterize your lawn mower after one last mow. Put away your lawn furniture. Then and only then can you take off your gardening gloves and consider your garden put to bed. Now you can sit back and relax your aching back – you deserve it.

Bruce McDonald is chief propagator and an educational instructor at VanDusen Botanical Garden.