When to Plant Petunias in Philomath, OR

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.

A common way of estimating when it's possible to plant petunias is to consult the USDA zone info for Philomath.


Planting Calendar for Petunias

Frost tolerance for petunias: Tolerant of a very small amount of frost.
When to plant: Up to 3 weeks before last frost.

Petunias do ok in moderate cold which tells us that you can plant them slightly earlier than more sensitive plants.

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

The earliest that you can plant petunias in Philomath is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant petunias and expect a good harvest is probably August. You probably don't want to wait any later than that or else your petunias may not have a chance to really do well. You can get started a little bit earlier by starting your petunias indoors.

Last Frost Date

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

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Philomath and it will vary from year to year. Half of the time in Philomath there is a last frost after March 15 so just be sure to be ready to protect your petunias in the event of a surprise late frost.

USDA Zone Info for Philomath

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 Philomath

You may be interested in your other planting guides for Philomath.