The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's a good idea to figure out when to plant impatiens by reviewing the USDA zone info for Lake Oswego.

Planting Calendar for Impatiens

Frost tolerance for impatiens:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Since impatiens do not do well in cold weather you must wait until after the last frost has passed before you can plant them.

The earliest that you can plant impatiens in Lake Oswego is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant impatiens and expect a good harvest is probably August. Any later than that and your impatiens may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your impatiens indoors.

Last Frost Date

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

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Lake Oswego and it can change quite a bit from year to year. Half of the time in Lake Oswego it frosts late in the year after March 15 so make sure that you are prepared to cover your impatiens if you have a late frost.

USDA Zone Info for Lake Oswego

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 Lake Oswego

You may be interested in your other planting guides for Lake Oswego.