When to Plant Asters in Coos Bay, OR

One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. 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 it's possible to plant asters is to refer to the USDA zone info for Coos Bay.


Planting Calendar for Asters

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

Asters can survive in some cold which means that you can plant them a bit earlier in the year than more sensitive plants.

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

The earliest that you can plant asters in Coos Bay is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant asters and expect a good harvest is probably October. If you wait any later than that and your asters may not have a chance to fully mature. If you are starting your asters indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost has passed is on February 15 in Coos Bay. You can expect an average low temperature of 20°F in the coldest months of winter.

It's important to remember that USDA zone info for Coos Bay is just an average and the actual date of last frost is different every year. Half of the time in Coos Bay you get a frost after February 15 so make sure that you are prepared to cover your asters if you have a late frost.

USDA Zone Info for Coos Bay

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)February 15
Average Date of First Frost (fall)December 15
Lowest Expected Low20°F
Highest Expected Low25°F

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

Plants to Grow in Coos Bay

You may be interested in your other planting guides for Coos Bay.