When to Plant Osteospermum in Mill Creek, WA

One of the first steps you take when you are figuring out 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.

The USDA zone info for Mill Creek can be reviewed to figure out when it's a good idea to plant osteospermum.


Planting Calendar for Osteospermum

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

Osteospermum are moderately cold tolerant which means that you can plant them earlier than plants that are more sensitive to the cold.

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

The earliest that you can plant osteospermum in Mill Creek 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 osteospermum and expect a good harvest is probably September. You probably don't want to wait any later than that or else your osteospermum may not have a chance to grow to maturity. Starting your osteospermum indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Mill Creek the average date of last frost happens on March 15. It might get as low as 15°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Mill Creek is just an average and the actual date of last frost will vary from year to year. Half of the time in Mill Creek there is a last frost after March 15 so just be sure to be ready to protect your osteospermum if you have one of those late frosts.

USDA Zone Info for Mill Creek

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 Low15°F
Highest Expected Low20°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 Mill Creek

You may be interested in your other planting guides for Mill Creek.