August Gardening Tasks For The Northern Rockies And Great Plains

Person In The Garden With A Box Of Vegetables
(Image credit: fergusowen)

Summer is winding down, but in August, there’s still ample time to take care of important gardening tasks for the northern Rockies. August in the west, north-central regions means it’s time to enjoy the last days of summer, and to prepare for cold weather right around the corner.

Here is your August garden to-do list.

Gardening Tasks For The Northern Rockies: Garden To-Do List

  • Pay extra attention to container-grown plants. Most need watering daily, and possibly twice during warm, dry spells. Hanging baskets dry quickly in sun and wind. Continue to feed container plants regularly, using a water-soluble fertilizer.
  • Don’t feed trees or shrubs as they begin preparing for winter dormancy. Fertilizing triggers tender new growth that is likely to be nipped by frost.
  • Continue to deadhead annuals and perennials regularly to trigger blooms until the first freeze.
  • Don’t let weeds get the upper hand. Gardening tasks for the northern Rockies should include the removal of weeds before they go to seed.
  • Remove annuals that didn’t survive the summer heat. Replace them with bright, late-summer or autumn annuals such as marigolds, zinnias, or salvia. By the time August rolls around, you can usually pick up annuals at a discounted price.
  • Check your garden daily and harvest vegetables at their peak of ripeness. Don’t leave those veggies too long, or they’ll become mushy, woody, or bitter. Harvesting zucchini and other summer squash every day or two will force the plants to keep producing. 
  • Cold weather arrives early in the northern Rockies, so check the weather report frequently during August in the west north-central regions. Harvest peppers, tomatoes, and other tender vegetables before the first frost, ideally before temperatures drop below 40 to 50 F. (4-10 cm.)
  • Water plants early in the morning so the roots can absorb moisture before the mid-day heat has time to dry the soil. Watering early also allows foliage to dry before evening, as wet foliage invites fungal disease and other problems.
  • Your garden to-do list for August should include replacement of mulch that has blown away or decomposed. A layer of mulch will keep the soil cooler, prevent moisture evaporation, and will also help staunch growth of weeds. 
Mary H. Dyer

A Credentialed Garden Writer, Mary H. Dyer was with Gardening Know How in the very beginning, publishing articles as early as 2007.