It’s Never Too Late to Add a Perennial

August is always a great time to take stock of the garden and take a good objective look as to where we have gaps, lack of colour or perhaps just need to change it up a bit.  Sometimes the addition of a heat pump or a deck requires some screening to cover the mechanics, sometimes tree growth has increased the amount of shade, or conversely, a tree has been removed and a former shady area is now full sun. Regardless of the reason, great deals on perennials are available now.

One of my favourite plants is Karl Foerster grass.  Super hardy and easy to grow, Karl Foerster is an early season grass often being up to my knees in June before a lot of other grass varieties are even showing.

Karl Foerster has a vey upright growing habit, one I often compare to having a Mountie standing at attention.  Its narrow foliage will reach a height of four feet with a spread of two feet.  In July, its narrow Timothy-like flowers appear in a silvery purple colour which mature to a golden wheat shade by fall.  It is very wind tolerant, disease and insect free and zone hardy.

Karl serves as a wonderful screen, either creating privacy or hiding eyesores.  It gives height in a perennial bed but is also one of the few grasses that will overwinter in containers, and if you’ve never grown grasses before, this is the one to start with.

If you’re tired of taking the hose or watering can to the end of the driveway to moisten the annuals around the mailbox or entry garden, consider planting Moonbeam yarrow.  Large, three-inch sulphur yellow flowers contrast against bright silver foliage.  This plant begins to flower in June and continues all the way to late September.  It is salt, wind and drought resistant and will grow poor soil, although it performs best in soil amended with lots of compost and peat.  Monthly deadheading only increases its showiness. It’s not unusual for this plant to reach a height and spread of two feet.

For those of you who are interested in native plants, you might consider planting a Tiarella.  This North American woodland beauty forms a thick mound of margined leaves, sometimes having many different colours.  The multiple stems of soft white flowers begin in June and will continue through the summer if deadheaded.  Tiarella grows best in part sun/part shade and will reach a height of one with a spread of twenty inches.

If you have a lot of colour in the Spring but need something for the end of season, consider growing Autumn Joy sedum.  This huge succulent has green broccoli-like flowers that ripen to bright pink and last until a killing frost.  Disease, insect and drought tolerant, this plant will add weight and substance to any garden, reaching a height and width of two feet.

These four perennials are long lasting, easy to grow and available to be planted now!

Garth Davey, August 2021
Questions? Email Garth at

Karl Foerster Feathered Reed Grass