What should I plant in September in Denver, CO?

In September in Denver, CO (zone 5b), you can plant Cilantro, Beet, Radish, Turnip, and more. These dates are based on local climate data for your area.

When do I plant Cilantro in Denver, CO?

In Denver, CO (zone 5b), Cilantro: direct sow Mar 17 – Jun 15 and Sep 1 – Sep 23.

When do I plant Beet in Denver, CO?

In Denver, CO (zone 5b), Beet: direct sow Mar 24 – Sep 8.

When do I plant Radish in Denver, CO?

In Denver, CO (zone 5b), Radish: direct sow Mar 24 – Jun 15 and Sep 1 – Sep 30.

What to Plant in September

Denver, CO · Zone 5b

Last frost: May 5 Frost-free days: 154

Full year calendar for Denver

The first frost is approaching. Finish up fall plantings and protect tender crops. Garlic goes in the ground this month or next. Harvest and preserve summer bounty.

September at a Glance

Indoor Transplant Direct Sow

1 5 10 15 20 25

Cilantro

Beet

Radish

Turnip

Direct Sow 4

Plant these seeds directly into the soil outdoors.

Turnip

Mar 17 – Sep 23

9 per sq ft 30–60 days

Beet

Mar 24 – Sep 8

9 per sq ft 50–70 days

Cilantro

Sep 1–23

9 per sq ft 30–45 days

Radish

Sep 1–30

16 per sq ft 22–30 days

September Gardening Tips

Direct sow Beet, Radish, Turnip straight into the garden — no transplanting needed.
Protect tender crops from early frost with row cover — this can extend your season by several weeks.

Nearby Cities

Albuquerque NM · Zone 7a Salt Lake City UT · Zone 6b Omaha NE · Zone 5b Sioux Falls SD · Zone 4b Oklahoma City OK · Zone 7a Kansas City MO · Zone 6a

Related Guides

Spacing Chart

How many plants per square foot

4×8 Raised Bed Layout

Planting plans for a standard bed

Planting Calendar

When to plant for your zone

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