When to Plant Black Eyed Susans in Castle Rock, CO

One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can figure out when to plant black eyed susans in Castle Rock by checking out the USDA zone info.


Planting Calendar for Black Eyed Susans

Frost tolerance for black eyed susans: Not tolerant of frost.
When to plant: After all chance of frost has passed.

It's probably not a good idea to plant black eyed susans until after all chance of frost has passed because they do not do well in cold weather.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant black eyed susans
Possibly ok, but a risky time to plant black eyed susans
Probably not a good time to plant black eyed susans

The earliest that you can plant black eyed susans in Castle Rock is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant black eyed susans and expect a good harvest is probably August. Any later than that and your black eyed susans may not have a chance to fully mature. If you are starting your black eyed susans indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Castle Rock. You should expect an average low temperature of -15°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Castle Rock and it can change quite a bit from year to year. Since half of the time in Castle Rock there is a last frost after April 15 be ready to cover your black eyed susans if you have a late frost.

USDA Zone Info for Castle Rock

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 Castle Rock

You may be interested in your other planting guides for Castle Rock.