When to Plant Sweet Williams in Hiawatha, IA

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

The USDA zone info for Hiawatha can be reffered to in order to figure out when to plant sweet williams.


Planting Calendar for Sweet Williams

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

You can plant sweet williams a bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

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

The earliest that you can plant sweet williams in Hiawatha 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 sweet williams and expect a good harvest is probably September. If you wait any later than that and your sweet williams may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your sweet williams indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Hiawatha. It might get as low as -20°F during the coldest months of winter.

Keep in mind that USDA zone info for Hiawatha is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Hiawatha you get surprised by a frost after April 15 so make sure that you are ready to protect your sweet williams if you have one of those late frosts.

USDA Zone Info for Hiawatha

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 Hiawatha

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