The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The best time to plant phlox in Happy Valley should be estimated by reviewing the USDA zone info.

Planting Calendar for Phlox

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

You can plant phlox a little earlier in the year because they are moderately cold tolerant.

The earliest that you can plant phlox in Happy Valley 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 phlox and expect a good harvest is probably September. You probably don't want to wait any later than that or else your phlox may not have a chance to grow to maturity. If you are starting your phlox indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average all chance of frost has passed is on March 15 in Happy Valley. In the coldest months of winter you should expect an average low temperature of 15°F.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Happy Valley and it can change quite a bit from year to year. Half of the time in Happy Valley last frost occurs after March 15 so make sure that you are ready to cover your phlox in the event of 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 Low	15°F
Highest Expected Low	20°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.