When to Plant Impatiens in Watertown, WI

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

You can determine when it's possible to plant impatiens in Watertown by reviewing the USDA zone info.


Planting Calendar for Impatiens

Frost tolerance for impatiens: Not tolerant of frost.
When to plant: After all chance of frost has passed.

Since impatiens are not cold tolerant it is important to wait until after the last frost has passed before you can plant them.

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

The earliest that you can plant impatiens in Watertown 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 impatiens and expect a good harvest is probably August. Any later than that and your impatiens may not have a chance to really do well. If you are starting your impatiens indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Watertown the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -20°F.

Just be sure 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 Watertown and it will vary from year to year. Since half of the time in Watertown it frosts late in the year after April 15 be ready to cover your impatiens if you have a late frost.

USDA Zone Info for Watertown

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-20°F
Highest Expected Low-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Watertown

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