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.

The USDA zone info for Zone 4b should be used to estimate when you can plant armeria.

Planting Calendar for Armeria

Frost tolerance for armeria:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Armeria can survive in quite a bit of cold which tells us that you can plant them much earlier in the year than other plants that might not handle the cold.

The earliest that you can plant armeria in Zone 4b 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 armeria and expect a good harvest is probably August. You probably don't want to wait any later than that or else your armeria may not have a chance to really do well. Starting your armeria indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is May 15 in Zone 4b. In the coldest months of winter you can expect an average low temperature of -25°F.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Zone 4b and it can change quite a bit from year to year. Half of the time in Zone 4b last frost occurs after May 15 so make sure that you are prepared to protect your armeria in the event of one of those late frosts.

USDA Zone Info for Zone 4b

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Zone 4b

You may be interested in your other planting guides for Zone 4b.