Pacific Northwest Gardener's August Checklist

In the event the Northwest has not seen sunny skies and dry summer weather nonetheless, we will in August. This is the month once the ground begins to bake, and it’s easy to become concerned that our plants won’t endure the yearly cycle of drought as well.

Yet August’s dry weather really is necessary for many crops to create a successful transition between seasons. Spring bulbs require that baking-hot soil to go 100 percent dormant and prepare for the next year’s bloom. Pears, peaches, plums and apples all require the extra boost of dry heat to ripen well. And onion crops, exactly like spring bulbs, choose energy out of their foliage this month to create those savory principles of the kitchen.

Jobs in ornamental gardens comprise staking dahlias along with other flowers to prevent flopping, removing spent flowers from roses and perennials, and cutting back daylilies which have gone summer dormant.

From the fruit and veggie garden, now is the time to begin eliminating fruited canes out of raspberries and thinning the patch. It’s also time to stop watering onions so they will go dormant and set a good harvest. And August is a great time to check out what is blooming at the nursery school. Scotch heather (Calluna vulgaris) is a colorful evergreen bloomer which does a great job filling in the time between the intermittent blooms of summer-flowering perennials.

Genevieve Schmidt

Stake flopping perennials. Dahlia (Dahlia cvs.) , Joe Pye weed (Eupatorium purpureum), Sedum (Sedum ‘Autumn Joy’ is shown) along with other tall bloomers often need help to stay upright in late summer, as their blooms can be thicker than their stems can bear. Plant bets and supports can be incredibly valuable in maintaining your crops out of flopping or even breaking up under the weight of summer blossoms.

These elegant English Y-stakes out of aHa! Modern Living are powerful enough to support crops, yet attractive enough to leave in the garden year-round if desired.

Timothy Lee landscape layout

Remove spent flowers. Keep on deadheading roses, Shasta daisies (Leucanthemum x superbum), dahlias along with other summer-flowering plants. By eliminating flowers, you encourage the plant to keep on setting new buds and put energy into flowers for the remainder of the summer.

As plants begin to eliminate steam, a dose of natural fertilizer can keep them moving faster. Pick one tagged for flowering plants; it’ll have exactly the ideal nutrients to excite blooms, rather than just foliage.

Barbara Pintozzi

Groom daylilies as necessary. Some types of daylily (Hemerocallis cvs.) Go dormant in summer, especially in gardens in which they aren’t watered regularly. If your daylily is appearing more brown than green, you have two choices: painstakingly pick out all of the brown foliage and expect the plant fills in, or just cut the entire thing down to the ground. When pruned to the ground in summer, daylilies grow back as soon as cool temperatures resume and will often offer a beautiful fall season of color.

Beertje Vonk Artist

Thin raspberries and begin onion harvesting. Now is also the time of year to care for some of your plants that are edible. Prune out any canes in your raspberry plants which have fruited, as the canes are most productive in their first year of fruit production. Only cut the fruited stems to the ground once they’re done bearing for year.

Onions can also use some attention right now, or instead, a lack of this. Stop watering onions if their stems turn yellow to force them into dormancy, and push the stems over to the ground to begin their ripening procedure. Leave them for about ten days, then dig them up (stems intact) and let them dry in a warm, airy place until the stems have the skins are papery and glistening.

Genevieve Schmidt

Pick out new plants. August often marks a pause point in the garden between the initial flush of summer flowers and the late summer series of reblooming perennials. If your garden is looking drab, go outside to the nursery and pick up a few Scotch heathers (Calluna vulgaris ‘Long White’ is shown). The vast array of foliage and blossom colors match into every garden, and they are freshly in bloom so that you can choose the colors that work for you.

Another great plant for this time of year is that the new Encore Azalea, a reblooming Azalea that just keeps going. While it has the traditional spring flowers we expect in the Azalea, it also flowers through overdue summer/early fall. If your garden needs something taller than a 2-foot heather, an Encore Azalea could fill the bill.

While August’s dry heat can be worrying for anglers, just remember it is a natural part of our climate and a great excuse to get outdoors and enjoy the warmth.


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