One of the best tools that you have as gardeners to help us estimate 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.

You can estimate when it's possible to plant sweet sultan in Humboldt by using the USDA zone info.

Planting Calendar for Sweet Sultan

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

Sweet Sultan do ok in a tiny bit of cold which tells us that you can plant them slightly earlier in the year than other plants that might not handle the cold.

The earliest that you can plant sweet sultan in Humboldt 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 sweet sultan and expect a good harvest is probably August. If you wait any later than that and your sweet sultan may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your sweet sultan indoors.

Last Frost Date

The average date of last frost is April 15 in Humboldt. It might get as low as 0°F during the coldest months of winter.

Since the USDA zone info for Humboldt is not always accurate the actual date of last frost is different every year. Half of the time in Humboldt there is a last frost after April 15 so make sure that you are prepared to cover your sweet sultan if you have a surprise late frost.

USDA Zone Info for Humboldt

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 Humboldt

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