One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By using the USDA zone info for Rupert you will be able to determine when it's possible to plant phlox.

Planting Calendar for Phlox

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

You can plant phlox just a bit earlier in the year because they do well in moderate cold.

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

Last Frost Date

In Rupert the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -10°F.

Keep in mind that USDA zone info for Rupert is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Rupert you get surprised by a frost after April 15 so always be ready to protect your phlox in the event of one of those late frosts.

USDA Zone Info for Rupert

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 Rupert

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