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 figure out when to plant regal geranium by looking at the USDA zone info for Humboldt.

Planting Calendar for Regal Geranium

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

Since regal geranium are barely cold tolerant you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant regal geranium in Humboldt 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 regal geranium and expect a good harvest is probably August. Any later than that and your regal geranium may not have a chance to fully mature. You can get started a little bit earlier by starting your regal geranium indoors.

Last Frost Date

The average date of last frost is April 15 in Humboldt. It might get as low as 0°F during the coldest months of winter.

Keep in mind that USDA zone info for Humboldt may not be accurate from year to year and the actual date of last frost changes from year to year. Half of the time in Humboldt there is a last frost after April 15 so just be sure to be ready to protect your regal geranium if you have a late frost.

USDA Zone Info for Humboldt

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Humboldt

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