When to Plant Sweet Peas in Manhattan, IL

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.

A common way of determining when it's a good idea to plant sweet peas is to refer to the USDA zone info for Manhattan.


Planting Calendar for Sweet Peas

Frost tolerance for sweet peas: Tolerant of a very small amount of frost.
When to plant: Up to 3 weeks before last frost.

Since sweet peas are barely cold tolerant you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant sweet peas
Possibly ok, but a risky time to plant sweet peas
Probably not a good time to plant sweet peas

The earliest that you can plant sweet peas in Manhattan 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 sweet peas and expect a good harvest is probably August. If you wait any later than that and your sweet peas may not have a chance to grow to maturity. You can get started a little bit earlier by starting your sweet peas indoors.

Last Frost Date

In Manhattan the average date of last frost happens on April 15. You should expect an average low temperature of -15°F in the coldest months of winter.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Manhattan and it will vary from year to year. Since half of the time in Manhattan there is a last frost after April 15 be ready to cover your sweet peas in the event of a surprise late frost.

USDA Zone Info for Manhattan

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 Manhattan

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