When to Plant Four-o-clock flower in Happy Valley, OR

One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first chance to plant four-o-clock flower in Happy Valley can be figured out by looking at the USDA zone info.


Planting Calendar for Four-o-clock flower

Frost tolerance for four-o-clock flower: Not tolerant of frost.
When to plant: After the last frost has passed.

It's probably not a good idea to plant four-o-clock flower until after the last frost because they require warm weather.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant four-o-clock flower
Possibly ok, but a risky time to plant four-o-clock flower
Probably not a good time to plant four-o-clock flower

The earliest that you can plant four-o-clock flower 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 four-o-clock flower and expect a good harvest is probably August. Any later than that and your four-o-clock flower may not have a chance to really do well. You can get started a few weeks earlier by starting your four-o-clock flower indoors.

Last Frost Date

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

Keep in mind that USDA zone info for Happy Valley may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in Happy Valley last frost occurs after March 15 be ready to protect your four-o-clock flower in the event of one of those late frosts.

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.