One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You will be able to determine when to plant armeria by using the USDA zone info for Janesville.

Planting Calendar for Armeria

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

Armeria are one of those plants that can tolerate quite a bit of cold weather which tells us that you can plant them a quite a bit earlier than other frost tender plants.

The earliest that you can plant armeria in Janesville 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 armeria and expect a good harvest is probably September. Any later than that and your armeria may not have a chance to really do well. If you are starting your armeria indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Janesville. You can expect an average low temperature of -20°F in the coldest months of winter.

Since the USDA zone info for Janesville is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Janesville it frosts late in the year after April 15 be ready to protect your armeria if you have a late frost.

USDA Zone Info for Janesville

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Janesville

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