One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You should be able to figure out when it's possible to plant argyranthemum by reviewing the USDA zone info for Waterloo.

Planting Calendar for Argyranthemum

Frost tolerance for argyranthemum:	Not tolerant of frost.
When to plant:	After the last frost.

Argyranthemum do not do well in cold weather which tells us that it is important to wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant argyranthemum in Waterloo 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 argyranthemum and expect a good harvest is probably August. If you wait any later than that and your argyranthemum may not have a chance to grow to maturity. If you are starting your argyranthemum indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Waterloo. It might get as low as -20°F during the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Waterloo and it can change quite a bit from year to year. Since half of the time in Waterloo there is a last frost after April 15 be ready to cover your argyranthemum if you have a late frost.

USDA Zone Info for Waterloo

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 Waterloo

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