Planting calendar
August Planting Guide for Denver, CO: Raised Beds, Containers & In-Ground
In August in Denver, focus on planting cool-season crops and preparing for fall harvests in raised beds, containers, and in-ground gardens. This is a great time to sow leafy greens, root vegetables, and herbs that mature before the first frost. Avoid heat-sensitive plants and start planning for fall by starting some seeds indoors.
Plant now (quick list)
lettuce, spinach, radishes, kale, beets, carrots, turnips, Swiss chard
Plant now
- lettuce
- spinach
- radishes
- kale
- beets
- carrots
- turnips
- Swiss chard
Start indoors
- broccoli
- cauliflower
- cabbage
- kohlrabi
- brussels sprouts
- lettuce
- spinach
Avoid
- tomatoes
- peppers
- eggplants
- summer squash
- cucumbers
- beans
Next 2 weeks
- plant fall crops in well-drained soil
- water raised beds and containers deeply in the morning
- mulch to conserve moisture and regulate soil temperature
- monitor for pests like aphids and caterpillars
- thin seedlings to prevent overcrowding
- fertilize leafy greens with nitrogen-rich fertilizer
FAQs
When is the first frost expected in Denver?
Typically, the first frost occurs in mid to late September, so plan fall crops accordingly.
Can I still plant tomatoes in August?
It's best to avoid planting tomatoes now as they require a long growing season and warm temperatures.
How often should I water container plants in August?
Water containers daily or whenever the top inch of soil feels dry, as they dry out faster in summer heat.
What soil preparation is recommended for fall planting?
Amend soil with compost and ensure good drainage to support healthy root development.
Are there any pests I should watch for in August?
Yes, monitor for aphids, cabbage worms, and flea beetles, especially on leafy greens.
Next steps
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