Fall Garden Tasks

By Brenda Evans

Let’s face it, it’s fall. It’s time to take a stroll through your garden and consider how it performed this year. What you were happy with? What would you like to change for next year? Are there plants that might perform better in another location? Are there any areas that are lacking seasonal colour or interest? It may come in handy to note this information in your gardening journal to refer to when planning for next year in the dead of winter.

While on that stroll, consider the garden cleanup that must be done. Below is a list of tasks to consider that may or may not apply to your garden.

Photo: Gosia Barrette

General Tasks

When it comes to general cleanup, there are a few things to attend to:

1. Check for and pull any weeds in the garden one last time. Unless there is a sign of disease or pest damage, there’s no need to cut down perennials and grasses and remove all plant debris. Hollow plant stems or debris under plants will provide a place for beneficial insects to overwinter. Seed heads and the tiny bugs that house in them are a food source for birds. Exceptions to this rule are that the leaves of irises and peonies should be cut back after the frost has turned the leaves brown. To read about the importance of what NOT to cleanup, read here.
2. Fallen leaves can be collected with your lawn mower and used as mulch. The mulch can be spread on the garden bed for insulation, prevention of weed growth, and to promote root growth. For more information on leaf mulch, read here.
3. Once their foliage has been hit by the first frost, dig up tender “bulbs” that require overwintering such as canna and dahlia. Brush off any soil and allow them to dry before storing in newspaper or sawdust in a cardboard box or bag. Keep it in a cool area until spring; check periodically for moisture levels, remove any that appear to be rotting, or mist any that appear to be wrinkled and drying up. See articles “About Overwintering Tropicals” and “A Love Affair with Dahlias”.
4. Take advantage of the fall sales in many nurseries and plant trees, shrubs, and perennials up six to eight weeks before the ground freezes. Water and mulch the plants, spreading two to three inches of mulch evenly around the base of the plants. Don’t pile the mulch on top of plants to avoid the risk of developing crown rot and pull the mulch away in the spring to allow the sun to warm the soil surface.
5. Watering the trees deeply before the ground freezes will give the roots access to the moisture in early spring before the ground thaws. The soil should be moist one to two feet down.
6. Mow your lawn once more, on the low setting. Rake the grass to prevent breeding grounds for voles or other pests and diseases and to loosen the top layer of soil. A fall application of fertilizer will promote root development. Overseeding your lawn before winter will allow the spring melt and the change in temperature to germinate the seeds early in the spring.
7. Clean and sharpen your gardening tools to maintain and keep them in good working condition. Update your tool inventory and note any that may need replacing. Hang them inside your garage or shed to keep dry. If you choose to clean and sharpen later, at least hang them inside your garage or shed in the meantime to protect them from the elements.
8. Turn off the outdoor water connection and remove and drain the garden hose. If the hose isn’t housed on a reel in a container, wind it up for indoor storage.

The Vegetable Garden

Harvest vegetables and herbs to store, preserve, or freeze. Master Gardener Janet Epp suggests that when removing crops, cut off the plants at soil level, leaving the roots in the soil to decompose. Plant debris should be cleaned up to prevent disease and insect pests in your vegetable garden, leaving straw and grass clippings in place. She recommends seeding a green manure crop on top of the roots to provide organic matter and add nutrients back in the soil. There are several options of green manure but choose one with a seed mix of legumes and other plants that have long tap roots to enrich and even loosen even clay soil while enriching it. If it blooms it should be deadheaded to prevent the spread of seeds. Cover the planting rows with compost before snowfall. Replenishing the soil with compost also empties the compost bin to make room for winter composting. To read about urban vegetable gardener Linda Cameron’s experience with cover crops, read here.

The Perennial Garden

1. Fall is the time to plant spring-blooming bulbs and garlic. Spring bulbs need several weeks of cold temperatures before they break their dormancy to bloom, and this gives them time to set roots before the cold weather sets in. Examples of spring bulbs are tulips, irises, daffodils, and allium. As a rule of thumb, bulbs can be planted at three times the depth of their height.
2. Collect your favourite flower seeds. Spread them out on newspaper to dry before storing in airtight containers in a cool, dry place. Be sure to label the containers.
3. Gather cut branches or dried flowers to use for outdoor pots or bring in for home decorations. Inspect them to ensure you’re not bringing in any unwanted guests. Read more here.
4. Dig up and divide clumps of perennials. Fall is a good time for transplanting. For more on dividing perennials, read here.
5. Transplant perennials that were in containers back into the garden for overwintering. They can be potted up again next spring or left where they’ve been planted.
6. Direct seed native plants that need cold stratification. When seeding in late fall, packing isn’t required because the melting snow and rain will work the seed into the soil.

The Container Garden

1. Clean out containers that had annual plants in them. The plant can be composted while the pots should be cleaned before storing for winter. Porous pots such as clay and ceramic will retain moisture and crack more easily if left outside over winter.
2. Bring in any houseplants that you took outside for the summer and any other plants that can be overwintered indoors as houseplants such as succulents or herbs such as rosemary. Group them together, repot them, spray them with water, and inspect them carefully for insects. Dispose of any diseased parts and spray with insecticidal soap.
3. Provided that the plants were not infected with disease or pest infestation, potting soil from containers can be sorted to be rid of debris and stored to be used in the bottom third of the pot next year.

The Water Features

1. To shut down any water features you must first remove any pump, filters, and electronics. They need to be cleaned and stored indoors during the winter months to prevent freezing and damage.
2. Fountains should be drained and covered with burlap to help prevent any water from accumulating and damage occurring from the freezing and thawing cycle.
3. For a detailed description of how to shut down your pond before winter, read here.