VIU Milner Gardens and Woodland

March Garden Tasks

by Vancouver Island Master Gardeners Association


March is much like the proverbial teen: stormy, calm, nasty, lovely and unpredictable. Our growing season begins during the first 3 days of the month – as the blooming Erica, galanthus, crocus and primula can attest – yet our frost date is mid-April. Frost date is an average and can vary as much as 2 weeks in the annual cycles. Until the third week a few degrees either way or a metre shift left or right can make the difference between a prized tender perennial overwintering or freezing, an early vegetable thriving or struggling, or a seedling tray failing. So, with the row cover at ready, and all the pots lined up to catch the sun, our monthly tasks can begin.

First, Check Those Winter To-Do Lists

There will be some February chores you didn’t get to. Cold and rainy days are good for finishing the tool sharpening, unkinking hoses in the garage, checking for trellis repair, making collars from old yogurt containers to protect young plants from marauding slugs, and unrolling / mending row cover and cloches.

Prep, Repair and Planting – Outdoors

  • Week by week prune shrubs as buds break: honeysuckle, clematis according to Group, all bush fruits (like currants and gooseberries) Ribes, and Vaccinium berries.
  • Repair-prune any shrubs broken from February’s late snowfall.
  • Check your early bulbs, making sure they are well seated in the soil: some will be a little heaved up from winter, and the returning birds will be pecking around the edges for grubs, doing damage.
  • Divide hosta, daylily, iris, mums
  • After compost is spread, turn under green manure crops, and throw down phacelia or other green manures in your fallow areas
  • Make sure nesting boxes, hummingbird and other feeders are sterilized, filled, and hung out, as the robins, rufus, and jays are returning and getting ready to nest. Put fresh sawdust in the nesting boxes.

Prep, Plan and Planting – Indoors

Bring your overwintered tender perennials out of dormancy. Water with warm water, then in a day or so give another watering with ¼- ½ strength organic balanced liquid fertilizer. DO NOT put outside unless the day is bright and the plant protected from wind.

At the end of the month, pot up tomatoes, planting them up to 1st leaves. The buried stalks will grow roots & develop a better root system. You will not set these out until late May so better to pot up one more time as late as April rather than shock the plants into cold soil and end up with a poor harvest from weak plants.

Prep, Plan and Planting – Under cover

Begin succession planting seeds in flats

  • Week 1: broccoli, cauliflower, cabbage, celery, peppers, the first group of lettuces, dill, sunflowers, annuals like marigolds and hanging basket flowers, and all your pollinator plants, like alyssum, candytuft
  • Week 2-3: mid-season tomato, more basil, lettuces & oriental greens, beets, summer cabbages & cauliflower
  • Week 4-5: cucumbers, summer squash, pumpkins, melons, more brassicas, more annual or tender herbs, harden off marigolds.

At month end, begin to harden off first group of veggies and annuals, protecting them at night or bringing them inside. Placing trays and pots on wagons or hand carts makes the job easier.

I Forgot!

If you forgot to prune late-flowering shrubs, you can trim them lightly if they are not yet growing. They may be a bit leggy this year, but you can prune a little harder this autumn. If you’ve discovered forgotten bulbs, plant them in ground or in pots. They will grow, but may not flower until next year.

 And finally - watch the storms, walk in the forest and marvel as the moss glows in its fruiting season. Count the crocus, smile at the early primula.