When to Plant Hollyhocks in Louisville, 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.

The USDA zone info for Louisville should be looked at to estimate when it's the best time to plant hollyhocks.


Planting Calendar for Hollyhocks

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

Hollyhocks tend to make it in a little bit of cold which means that you can plant them a little bit earlier in the year than plants that are more sensitive to the cold.

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

The earliest that you can plant hollyhocks in Louisville 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 hollyhocks and expect a good harvest is probably September. You probably don't want to wait any later than that or else your hollyhocks may not have a chance to fully mature. You can get started a few weeks earlier by starting your hollyhocks indoors.

Last Frost Date

The average date of last frost is April 15 in Louisville. You can expect an average low temperature of -10°F in the coldest months of winter.

Remember that USDA zone info for Louisville may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in Louisville there is a last frost after April 15 be ready to protect your hollyhocks in the event of one of those late frosts.

USDA Zone Info for Louisville

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-10°F
Highest Expected Low-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Louisville

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