When to Plant Phlox in Grafton, WI

Before planting it is a good idea to find your USDA Zone info to figure out 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.

It's possible to determine when it's a good idea to plant phlox by referring to the USDA zone info for Grafton.


Planting Calendar for Phlox

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

Phlox do well in some cold which means that you can plant them just a bit earlier in the year than other plants that might not handle the cold.

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

The earliest that you can plant phlox in Grafton 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. Any later than that and your phlox may not have a chance to really do well. 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 April 15 in Grafton. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Grafton is just an average the actual date of last frost will vary from year to year. Half of the time in Grafton there is a last frost after April 15 so make sure that you are ready to cover your phlox in the event of a surprise late frost.

USDA Zone Info for Grafton

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-15°F
Highest Expected Low-10°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 -10°F.

Plants to Grow in Grafton

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