One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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 Raritan can be reffered to in order to determine when it's a good idea to plant dahlia.

Planting Calendar for Dahlia

Frost tolerance for dahlia:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Dahlia require warm weather which means that you have to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant dahlia in Raritan is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant dahlia and expect a good harvest is probably August. If you wait any later than that and your dahlia may not have a chance to really do well. If you are starting your dahlia 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 Raritan. It might get as low as -5°F during the coldest months of winter.

Remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Raritan and it changes from year to year. Half of the time in Raritan there is a last frost after April 15 so make sure that you are ready to cover your dahlia in the event of one of those late frosts.

USDA Zone Info for Raritan

Here is the info for USDA Zone 6b.

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

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

Plants to Grow in Raritan

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