Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of making a decision about when it's a good idea to plant primula is to look at the USDA zone info for Somersworth.

Planting Calendar for Primula

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

You can plant primula much earlier in the year because they are one of those plants that can tolerate quite a bit of cold weather.

The earliest that you can plant primula in Somersworth 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 primula and expect a good harvest is probably September. If you wait any later than that and your primula may not have a chance to fully mature. Starting your primula indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Somersworth. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Somersworth is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Somersworth it frosts late in the year after April 15 be ready to cover your primula if you have a surprise late frost.

USDA Zone Info for Somersworth

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Somersworth

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