When to Plant Argyranthemum in Happy Valley, OR

Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By looking at the USDA zone info for Happy Valley it's possible to estimate when to plant argyranthemum.


Planting Calendar for Argyranthemum

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

Argyranthemum do not do well in cold weather which means that you must wait until it warms up after the last frost before you can plant them.

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

The earliest that you can plant argyranthemum in Happy Valley 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 argyranthemum and expect a good harvest is probably August. If you wait any later than that and your argyranthemum may not have a chance to grow to maturity. If you are starting your argyranthemum indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is March 15 in Happy Valley. In the coldest months of winter you can expect an average low temperature of 15°F.

Since the USDA zone info for Happy Valley is not always accurate the actual date of last frost will vary from year to year. Half of the time in Happy Valley there is a last frost after March 15 so always be ready to protect your argyranthemum if you have a late frost.

USDA Zone Info for Happy Valley

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 Happy Valley

You may be interested in your other planting guides for Happy Valley.