What to plant this week in Denver, CO
With the last frost in Denver typically holding until April 21, this week marks the transition from hardening off late spring crops to a full swing in summer harvest. Gardeners across the Front Range are now focused on pulling the first yields of heat-loving giants like watermelon and okra while protecting sensitive greens from intense afternoon sun. The soil is warming up fast after our dry winter, making it critical to retain moisture as evaporation rates climb.
The next 7 days
Denver, COGrowing in Denver right now
- Denver's clay-loam mix holds water poorly in hot weather; soak beds deeply early morning rather than frequent shallow watering to avoid stress on beans and corn.
- The city's notorious drought conditions mean mulching is non-negotiable now to keep soil cool for edamame and squash roots.
- High altitude UV index peaks quickly after 10 AM; use shade cloth or sheer curtains for basil, lettuce, and shiso if temperatures hit the mid-80s.
- Watch out for late-season bolting in fennel and parsnip as day length shortens toward the Oct 17 frost date.
Sow this week
No direct sowing windows open this week.
Transplant this week
Nothing is due to go out this week.
Harvest soon
45 crops- Basil
- Borage
- Bush Bean
- Cantaloupe
- Celery
- Cleome (Spider Flower)
- Cosmos
- Cowpea (Black-Eyed Pea)
- Cucumber
- Dahlia
- Edamame
- Fennel
- Flour Corn
- French Marigold
- Garden Verbena
- Garlic
- Ghost Pepper (Bhut Jolokia)
- Gourd (Ornamental/Bottle)
- Honeydew Melon
- Leek
- Lima Bean
- Lisianthus (Prairie Gentian)
- Loofah (Luffa)
- Malabar Spinach
- Nasturtium
- Okra
- Ornamental Sweet Potato Vine
- Parsnip
- Pole Bean
- Potato
- Pumpkin
- Roselle (Cranberry Hibiscus)
- Scarlet Runner Bean
- Shiso (Japanese Basil)
- Summer Savory
- Sunflower
- Sweet Corn
- Sweet Potato
- Thai Basil
- Vinca (Madagascar Periwinkle)
- Watermelon
- Winter Squash
- Yellow Summer Squash
- Zinnia
- Zucchini
Seasonal tips
- Succession sow bush beans and sweet corn every two weeks for continuous harvests through summer.
- Pinch back the tips of basil and okra to encourage bushier growth rather than flowering too early.
- Add a thin layer of straw or shredded leaves around heavy feeders like pumpkins and squash to retain moisture.
Pest & disease watch
- Colorado potato beetles are exploding on your potato and tomato plants this week; hand-pick adults every morning before they lay eggs.
- Cucumber beetles target all cucurbits (cucumbers, squash, melons); row covers work best now that transplants are established.
- Spider mites thrive in Denver's dry heat, causing stippling on sunflower and zinnia leaves; a strong water spray or insecticidal soap helps.
Watering this week
Provide about 1 to 2 inches of water per week, applying it deeply in the morning to reduce evaporation and disease risk.
Harvest zucchini and summer squash early in the day when they are most tender and flavorful for your table.
Denver gardening questions
3Can I still plant garlic in Denver this week?
Yes, fall-planted garlic should be sown now before the ground freezes hard around late October. Choose a well-drained spot and dig deep enough to keep the cloves from rotting if heavy rains occur.
My pole beans are flowering but not setting pods; what's wrong?
It is likely too hot or the plants aren't pollinating due to lack of bees in our dry conditions. Water deeply once a week and consider hand-pollination with a small brush if flies are scarce.
When should I harvest my cantaloupe and honeydew melons?
Check for full color and a strong scent at the stem; tap them gently for a deep, hollow sound before the first frost on Oct 17. Leave some rind attached to protect them from birds as they ripen.
Other cities in zone 6a
12See the full zone 6a guide → · Plan your Denver garden in SproutGuide →