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.

You can figure out when it's possible to plant nigella in Amsterdam by checking out the USDA zone info.

Planting Calendar for Nigella

Frost tolerance for nigella:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Since nigella are very cold tolerant you can plant them much earlier in the year than more sensitive plants.

The earliest that you can plant nigella in Amsterdam 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 nigella and expect a good harvest is probably September. If you wait any later than that and your nigella may not have a chance to fully mature. If you are starting your nigella 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 when the weather gets warmer is on April 15 in Amsterdam. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Amsterdam is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Amsterdam it frosts late in the year after April 15 so always be ready to protect your nigella if you have a surprise late frost.

USDA Zone Info for Amsterdam

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Amsterdam

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