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 diascia in Columbus should be determined by referring to the USDA zone info.

Planting Calendar for Diascia

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

You can plant diascia just a bit earlier in the year because they are moderately cold tolerant.

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

Last Frost Date

In Columbus the average date of last frost happens on April 15. It might get as low as -10°F during the coldest months of winter.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Columbus and it can change quite a bit from year to year. Half of the time in Columbus you get surprised by a frost after April 15 so make sure that you are prepared to cover your diascia in the event of one of those late frosts.

USDA Zone Info for Columbus

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Columbus

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