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

You should be able to estimate when it's a good idea to plant columbine by using the USDA zone info for Arab.

Planting Calendar for Columbine

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

Since columbine do well in moderate cold you can plant them a little earlier in the year than more sensitive plants.

The earliest that you can plant columbine in Arab 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 columbine and expect a good harvest is probably September. Any later than that and your columbine may not have a chance to fully mature. Starting your columbine indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Arab the average date of last frost happens on April 15. It might get as low as 5°F during the coldest months of winter.

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

USDA Zone Info for Arab

Here is the info for USDA Zone 7b.

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

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

Plants to Grow in Arab

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