One of the first steps you take when you are making a decision about your gardening schedule is find your 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.

The first chance to plant crassula in Johnston can be estimated by referring to the USDA zone info.

Planting Calendar for Crassula

Frost tolerance for crassula:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

You really shouldn't plant crassula until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant crassula in Johnston is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant crassula and expect a good harvest is probably August. If you wait any later than that and your crassula may not have a chance to grow to maturity. Starting your crassula indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

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

Since the USDA zone info for Johnston is just an average the actual date of last frost is different every year. Half of the time in Johnston it frosts late in the year after April 15 so make sure that you are prepared to cover your crassula if you have a surprise late frost.

USDA Zone Info for Johnston

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 Johnston

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