VIU Milner Gardens and Woodland

October Garden Tasks

by Vancouver Island Master Gardeners Association

October – calendula, carrots, pumpkins, apples, scarlet maples and blue-violet asters. This month we divide perennials, begin raking leaves, put away the kids’ pool, and watch when the hazel trees turn colour to let us know the nuts are ready to harvest.

The smart gardener understands that the more we do now, the better our landscape will fare over winter, and healthier it will be come spring. Make a few notes to prioritize garden tasks between now and year’s end.


Continue Feeding the Soil, But Not the Plants

Many autumn jobs can be overlooked. This one cannot – it is absolutely essential. While finishing off the autumn task of rejuvenating soil with compost-enriched mulch, remember it can still be dry. Heavy watering and fertilizers after our heat dome summer drought and mild September can actually stress plants in a new way, and rob the soil of the oxygen it needs to regenerate the mycelium food web. Make sure your amendment is moist to the soil line so it will compost more quickly while the weather remains mild, and slow run-off from a heavy autumn downpour. If you have worm castings, toss a handful under the mulch near shrubs’ main stems.


The Joy of Leaves, the Magic of Compost

These are some of Mother Nature’s soil health heroes. As leaves fall, make your job easier and mix them into nearby mulch. Too many Leaves? Bag, adding a little of water to help start the mold, then store near the compost bin. You can toss a handful into the bin each time you add kitchen leavings to balance the mix or leave until next year to boost spring compost with the moldy mess for nutrient dense soil in both landscape and the veggie bed. The large maple stems make good mulch. If you add a lot of stone fruit or berry must from the autumn jamming to the bin, remember we have the bears who are hungry and urban. Mix lots of dirt with the chopped fruit to dampen odor, put in the centre of the bin mixed with and surrounded by leaves and other garden waste. The worms will migrate there in droves!


 Divide and Conquer

 If you are not sure when to divide your perennials, try this strategy from Tim Johnson, a senior director of horticulture for the Chicago Botanic Garden in Glencoe, Illinois: 

“… prune plants based on their bloom time. Late summer and fall blooming perennials … get divided in spring while spring and early summer flowering perennials get divided in fall.”

Here is a list of some common perennials to divide now:

  • Astilbe (Astilbe spp.)
  • Chives (Allium schoenoprasum)
  • Bleeding Heart (Dicentra spp., Lamprocapnos spectabilis
  • Lily of the Valley (Convallaria majalis)  
  • Oriental Lily (Lilium orientalis ‘Stargazer’) 
  • Veronica/speedwell (Veronica spicata
  • Rhubarb (Rheum rhabarbarum)


Along the Border

Plant wallflowers, primula, viola, winter pansies. In mild areas, sow hardy annuals to overwinter for next year’s blooms. Plant the first round of spring-flowering bulbs.


In the Veggie Garden

Plant garlic, early fava, more Walla Walla onions early in the month if mild, mache, pak choi, celeriac.

Protect cauliflower heads by breaking a couple of outer leaves mid-length and folding them over the flower. Secure in place by threading a twig through the leaves. Cole crops – cauliflower, broccoli, cabbage, Brussels sprouts – need consistent water this time of year. A feed of compost will help to sustain them as they grow through the winter. Row covers on leafy greens keep them producing, too, while protecting them from winter rains and wind.

Late Season Pest Patrol

Slugs, snails, and aphids are the primary autumn pests, but fall webworm is also heavy in the Cowichan Valley this year. A few small webs do little damage, but any pest that defoliates stresses the plant. In the veggie garden, set out wire worm traps using thick potato slices stuck into the oil around susceptible plants. The more you catch now, the fewer spring veggies you’ll lose next year.


Get Ahead of the Game

Empty summer container soil on to a tarp. Add up to 20% mixed amendment consisting of perlite or coir fibre for aeration, a bit of manure, compost, some shredded dry leaves, kelp meal (for minerals). Clean the containers. Refill pots 2/3 full and store in a dry spot. Next spring most of your job is done. Just fluff the soil, add a pinch of worm castings, tuck in new plants, and top up with over-wintered compost or new potting soil.


OMG I Forgot!

Dig and store tuberous begonia. The first frost may come mid-month but can hold off until November so there is still time. When the thermometer dips, dig and bring in to dry, shake off dirt, and store. There is still time to divide all iris. If clumps look poorly at the centre, they need attention or will have poor blooms and may develop disease next year.


And finally…

Instead of composting the cut-off arching pods of crocosmia and ornamental grass stems, spray them with artists’ fixative for a Thanksgiving bouquet that won’t shed or bother allergies. While the geese and songbirds are leaving and the salmon returning, sit on the patio and marvel at autumn’s changing palette and the taste of wine in the air, or go for a picnic in a park. When was the last time you jumped in a pile of leaves to revel in the aroma of musk and berry? These days are precious, and gone too soon.