Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant rhubarb in Colby can be figured out by looking at the USDA zone info.

Planting Calendar for Rhubarb

Frost tolerance for rhubarb:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant rhubarb a little bit earlier in the year because they do well in moderate cold.

The earliest that you can plant rhubarb in Colby 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 rhubarb and expect a good harvest is probably September. Any later than that and your rhubarb may not have a chance to grow to maturity. If you are starting your rhubarb indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost is on April 15 in Colby. You can expect an average low temperature of -15°F in the coldest months of winter.

Keep in mind that USDA zone info for Colby is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Colby last frost occurs after April 15 so always be ready to protect your rhubarb if you have a surprise late frost.

USDA Zone Info for Colby

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 Colby

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