Tips for helping your garden manage during the very hot, dry days ahead
August in Colorado is a season of harvest abundance but can also bring a string of very hot days (including next week per local predictions). To help your gardens manage, sustain plants through the heat with the tips below.
Watering & Mulching
Pest, Disease & General Maintenance
Flowers & Containers
Provide shade
Watering & Mulching
- Aim for deep, infrequent watering in the early-morning that moistens the soil several inches deep. This helps plants stay evenly moist where they need it most (the roots).
- Avoid wetting foliage by spraying from overhead with a hose, which can lead to fungal diseases like powdery mildew. Consider using soaker hoses or drip irrigation to deliver water at the soil level, or focus water from a hose at the soil level.
- Refresh mulch around plants and trees to retain moisture longer, suppress weeds, and keep soil temperatures moderated. Make sure mulch is applied away from stems to prevent rot.
- Remember to give trees and shrubs deep watering too.
- Harvest vegetables daily or every other day — especially tomatoes, zucchini, beans, and herbs. This will sustain fruit production and avoid over-ripeness or pest issues.
- Deadhead spent annuals and perennials to encourage more blooming. Prune summer‑flowering shrubs soon after they finish.
- Begin planting cool-season crops like kale, radish, lettuce, beets, peas and spinach so they have time to mature before our first hard frost in the Fall (late October).
- Apply a fertilizer to tomatoes, squash, and flowering veggies to sustain fruiting and flowering.
- For hot, dry days, the best fertilizer options are slow-release nitrogen fertilizers or those with a lower nitrogen content to prevent burning. Organic fertilizers like Milorganite can also be effective as they release nutrients slowly and can be more beneficial in high heat. Additionally, fertilizers containing humic acid can improve soil structure and water retention, helping plants better handle drought conditions. Fertilizers like Miracle Grow can be used but follow certain guidelines to avoid further stressing the plants:
- Apply any fertilizer in the early morning or late evening - never during the heat of the day. Additionally, ensure plants are well-hydrated before applying fertilizer is crucial because stressed plants prioritize water uptake over nutrient absorption. If the soil is already moist, they will be better able to take up the nutrients being applied.
- Apply any fertilizer in the early morning or late evening - never during the heat of the day. Additionally, ensure plants are well-hydrated before applying fertilizer is crucial because stressed plants prioritize water uptake over nutrient absorption. If the soil is already moist, they will be better able to take up the nutrients being applied.
Pest, Disease & General Maintenance
- Monitor for pests like aphids, spider mites, hornworms, and cucumber beetles; use organic controls (hand-picking, Neem spray, companion planting, soap sprays) as needed.
- Remove fallen fruit and spent vegetables promptly to deter pests and disease buildup.
Flowers & Containers
- There's still time to refresh faded annuals—replace heat-weary plants with late-summer bloomers like marigolds, salvia, zinnias, angelonia, or ornamental kale.
- Deadhead tired flowers and cut herbs or flowering growth to help re-bloom and preserve energy.
- Water containers daily—and possibly twice on hot days—checking soil moisture with the finger test or moisture meter to prevent drying or conversely root rot (from too much water) in pots and hanging baskets.
Provide shade
- .Use shade cloth, umbrellas, or other structures to protect plants from the intense sun and drying winds.
- If possible, move container plants to a cooler, shaded location during the hottest part of the day.
- Grouping containers together during hot spells can create a microclimate that retains more moisture.