Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. 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 you can plant yarrow is to consult the USDA zone info for Oswego.

Planting Calendar for Yarrow

Frost tolerance for yarrow:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Yarrow are very cold tolerant which means that you can get them planted much earlier than other plants that might not handle the cold.

The earliest that you can plant yarrow in Oswego 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 yarrow and expect a good harvest is probably September. Any later than that and your yarrow may not have a chance to fully mature. Starting your yarrow indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Oswego. In the coldest months of winter you should expect an average low temperature of -15°F.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Oswego and it will vary from year to year. Since half of the time in Oswego it frosts late in the year after April 15 be ready to cover your yarrow if you have a surprise late frost.

USDA Zone Info for Oswego

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 Oswego

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