When to Plant Osteospermum in Grafton, WI

One of the first steps you take when you are estimating your gardening schedule is find your 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.

The first chance to plant osteospermum in Grafton should be determined by reviewing the USDA zone info.


Planting Calendar for Osteospermum

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

Since osteospermum do well in moderate cold you can plant them just a bit earlier in the year than other frost tender plants.

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

The earliest that you can plant osteospermum 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 osteospermum and expect a good harvest is probably September. If you wait any later than that and your osteospermum may not have a chance to grow to maturity. Starting your osteospermum indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Grafton the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Grafton and it changes from year to year. Half of the time in Grafton you get a frost after April 15 so make sure that you are ready to cover your osteospermum if you have a 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.