One of the first steps you take when you are determining 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 USDA zone info for Olney should be read to figure out when to plant tall phlox.

Planting Calendar for Tall Phlox

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

You can plant tall phlox a little earlier in the year because they are moderately cold tolerant.

The earliest that you can plant tall phlox in Olney 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 tall phlox and expect a good harvest is probably September. You probably don't want to wait any later than that or else your tall phlox may not have a chance to really do well. If you are starting your tall phlox indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Olney. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Olney is an average the actual date of last frost changes from year to year. Half of the time in Olney last frost occurs after April 15 so make sure that you are prepared to cover your tall phlox if you have one of those late frosts.

USDA Zone Info for Olney

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 Olney

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