frostdate name logo in white
frostdate name logo in white

When to Plant Blue Lace Flowers in Boulder, CO

One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to estimate when you can plant blue lace flowers by referring to the USDA zone info for Boulder.


Planting Calendar for Blue Lace Flowers

Frost tolerance for blue lace flowers: Tolerant of a very small amount of frost.
When to plant: Up to 3 weeks before last frost.

Blue Lace Flowers do ok in a tiny bit of cold which means that you can plant them a bit earlier in the year than other plants that might not handle the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant blue lace flowers
Possibly ok, but a risky time to plant blue lace flowers
Probably not a good time to plant blue lace flowers

The earliest that you can plant blue lace flowers in Boulder is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant blue lace flowers and expect a good harvest is probably August. If you wait any later than that and your blue lace flowers may not have a chance to really do well. Starting your blue lace flowers indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Boulder the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -15°F.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Boulder and it changes from year to year. Half of the time in Boulder it frosts late in the year after April 15 so make sure that you are prepared to cover your blue lace flowers if you have a surprise late frost.

USDA Zone Info for Boulder

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 Boulder

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