One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of figuring out when to plant oriental poppies is to look at the USDA zone info for Cambridge.

Planting Calendar for Oriental poppies

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

Oriental poppies are moderately cold tolerant which means that you can get them planted earlier than other frost tender plants.

The earliest that you can plant oriental poppies in Cambridge 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 oriental poppies and expect a good harvest is probably August. You probably don't want to wait any later than that or else your oriental poppies may not have a chance to grow to maturity. If you are starting your oriental poppies 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 May 15 in Cambridge. You can expect an average low temperature of -30°F in the coldest months of winter.

Remember that USDA zone info for Cambridge is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Cambridge it frosts late in the year after May 15 so be sure to be ready to cover your oriental poppies if you have a late frost.

USDA Zone Info for Cambridge

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Cambridge

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