Before planting it is a good idea to find your USDA Zone info to determine your garden 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 determine when it's the best time to plant missouri primrose by using the USDA zone info for Worcester.

Planting Calendar for Missouri Primrose

Frost tolerance for missouri primrose:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant missouri primrose just a bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant missouri primrose in Worcester 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 missouri primrose and expect a good harvest is probably September. If you wait any later than that and your missouri primrose may not have a chance to grow to maturity. If you are starting your missouri primrose indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Worcester. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Worcester may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Worcester you get surprised by a frost after April 15 so always be ready to cover your missouri primrose in the event of a surprise late frost.

USDA Zone Info for Worcester

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 Worcester

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