When to Plant Lupine in Green River, WY

One of the best tools that you have as gardeners to help us figure out 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.

By reviewing the USDA zone info for Green River you should be able to determine when it's the best time to plant lupine.


Planting Calendar for Lupine

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

You can plant lupine a little earlier in the year because they are moderately cold tolerant.

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

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

Last Frost Date

On average the last frost has passed is on May 15 in Green River. It might get as low as -25°F during the coldest months of winter.

Since the USDA zone info for Green River is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Green River you get surprised by a frost after May 15 be ready to protect your lupine in the event of a late frost.

USDA Zone Info for Green River

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-25°F
Highest Expected Low-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Green River

You may be interested in your other planting guides for Green River.