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.

In Altus you can estimate when it's the best time to plant calendula by looking at the USDA zone info.

Planting Calendar for Calendula

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

Since calendula are one of those plants that can tolerate a little bit of cold weather you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant calendula in Altus 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 calendula and expect a good harvest is probably September. If you wait any later than that and your calendula may not have a chance to really do well. You can get started a little bit earlier by starting your calendula indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Altus. In the coldest months of winter you can expect an average low temperature of 5°F.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Altus and it can change quite a bit from year to year. Half of the time in Altus there is a last frost after April 15 so make sure that you are prepared to protect your calendula in the event of one of those late frosts.

USDA Zone Info for Altus

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 Altus

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