The USDA Zone info is a great tool for gardeners to help us determine 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 USDA zone info for Viroqua can be looked at to figure out when it's the best time to plant phlox.

Planting Calendar for Phlox

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

Since phlox do well in moderate cold you can plant them a little bit earlier in the year than more sensitive plants.

The earliest that you can plant phlox in Viroqua 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 phlox and expect a good harvest is probably August. Any later than that and your phlox may not have a chance to fully mature. You can get started a few weeks earlier by starting your phlox indoors.

Last Frost Date

The average date of last frost is May 15 in Viroqua. It might get as low as -25°F during the coldest months of winter.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Viroqua and it changes from year to year. Half of the time in Viroqua it frosts late in the year after May 15 so make sure that you are prepared to protect your phlox if you have a surprise late frost.

USDA Zone Info for Viroqua

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Viroqua

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