The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Douglas should be used to estimate when it's a good idea to plant alstromeria.

Planting Calendar for Alstromeria

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

Since alstromeria do well in moderate cold you can plant them a little bit earlier in the year than other frost tender plants.

The earliest that you can plant alstromeria in Douglas 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 alstromeria and expect a good harvest is probably September. You probably don't want to wait any later than that or else your alstromeria may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your alstromeria indoors.

Last Frost Date

The average date of last frost is March 15 in Douglas. You can expect an average low temperature of 15°F in the coldest months of winter.

Since the USDA zone info for Douglas may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Since half of the time in Douglas it frosts late in the year after March 15 be ready to protect your alstromeria in the event of a late frost.

USDA Zone Info for Douglas

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in Douglas

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