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Master gardener tips: Here's what you should do in your gardens this month

There are lots of things to do in August to get ready for fall planting
IMG_0302 John Hethrington, Past President, Master Gardeners of Ontario
John Hethrington is a Master Gardener living in Meaford where he tends 20 different gardens. Contributed photo

John Hethrington has been gardening since the age of nine. He started a career in gardening in high school and launched his own gardening service by Grade 12, and grew the business from there.

He spent his early life gardening in Toronto and earned his certification as a Master Gardener before moving to Meaford where he cultivates 2.5 acres with 20 different gardens including perennials, roses, a xeriscape garden, a meadow, two bog gardens, several shrub borders and a pond.


August is all about watering, weeding, and preparing for fall planting when it comes to gardening. Master Gardener John Hethrington suggests adding these gardening chores to your August to-do list.

  • Cold wet spring, followed now by a sweltering summer has made the weeds incredible.
  • Keep adding mulch as it starts to work into the soil. Keep it at least two-inches deep. It works to suppress weeds and keeps the soil cool and damp and protects any rain we get.
  • If we don’t get rain, water, water, water, but water deeply.
  • Sow vegetable seeds for a fall harvest e.g. spinach and some varieties of lettuce.
  • Tidy up plants and shrubs with a little judicious pruning, but early in the month.
  • Stake tall perennials against the wind.
  • Cut your grass at least two inches high to combat drying out. Water well when needed, or every time it’s allowed. 
  • Check out bulb catalogues
  • Order spring-flowering bulbs for planting in October.
  • Fill in gaps in your flower garden with fall-flowering perennials, like mums and asters.
  • Did I say, water and weed as necessary?
  • Start drying flowers and herbs.
  • Start to divide daylilies and peonies later in the month.
  • Collect seeds that have matured but not fallen from the plant. Once they have completely dried, store them in airtight containers in a cool location.
  • Take a hard look at your garden and decide where there are empty spaces, identify any plants that have not performed well and plan a fall planting program of shrubs and perennials.
  • Early fall is a great time to sow grass seed, plant perennials, trees and shrubs. You’ll get a big jump on next spring