When to Plant Fennel in Carbondale, CO

The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to figure out when it's possible to plant fennel by looking at the USDA zone info for Carbondale.


Planting Calendar for Fennel

Frost tolerance for fennel: Very tolerant of frost.
When to plant: Up to 7 weeks before last frost.

Fennel do well in quite a bit of cold which tells us that you can plant them much earlier in the year than plants that are more sensitive to the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant fennel
Possibly ok, but a risky time to plant fennel
Probably not a good time to plant fennel

The earliest that you can plant fennel in Carbondale is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant fennel and expect a good harvest is probably September. You probably don't want to wait any later than that or else your fennel may not have a chance to grow to maturity. If you are starting your fennel indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Carbondale. In the coldest months of winter you should expect an average low temperature of -15°F.

Since the USDA zone info for Carbondale is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Carbondale you get a frost after April 15 so make sure that you are ready to protect your fennel in the event of a late frost.

USDA Zone Info for Carbondale

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-15°F
Highest Expected Low-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Carbondale

You may be interested in your other planting guides for Carbondale.