Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Park Ridge you can figure out when it's a good idea to plant delphinium by reviewing the USDA zone info.

Planting Calendar for Delphinium

Frost tolerance for delphinium:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant delphinium just a tiny bit earlier in the year because they do ok in moderate cold.

The earliest that you can plant delphinium in Park Ridge is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant delphinium and expect a good harvest is probably August. You probably don't want to wait any later than that or else your delphinium may not have a chance to grow to maturity. If you are starting your delphinium 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 Park Ridge. It might get as low as 0°F during the coldest months of winter.

Remember that USDA zone info for Park Ridge is not always accurate and the actual date of last frost is different every year. Half of the time in Park Ridge you get surprised by a frost after April 15 so make sure that you are ready to protect your delphinium in the event of one of those late frosts.

USDA Zone Info for Park Ridge

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Park Ridge

You may be interested in your other planting guides for Park Ridge.