Imperial Star Artichoke Seeds

If you can't over-winter your artichokes or if you just want to grow them as an annual then this is the one for you. The 6-8 buds of the Imperial Star are nearly spineless, a globe-shape with up to 3-4 inches in diameter with a rich glossy green color. You will enjoy the same rich flavor that you expect in any artichoke. This variety will turn into a perennial for zones 7 and above. (Package 25 Seeds).

Vegetable Garden - Tips on Growing Imperial Star Artichoke From Seeds

The objective is to convince the Artichoke plant that it is two years old and ready to make buds, rather than a seedling ready to make only leaves. This is done by growing the plant at cool temperatures for a prescribed length of time. This cold treatment makes the seedling behave as if it is an older plant ready to flower.

Before you use the cold treatment here is information for sowing the seed.

Sowing the Artichoke Seeds

Artichoke Seed Depth: �" (6mm)
Germination soil temperature: 70-80�F (21-27�C)
Days to Germination: 10-14

Sow Indoors:

Late winter to early spring- 10 weeks before last frost.

Sow outdoors: Not recommended.

Growing Artichoke Seeds:

pH range: 6.5 - 8.0
Growing soil temperature: 60-75�F (16-24�C)
Spacing in beds: 24" (60 cm)
Watering: Heavy
Light: 8 hours or more per day
Nutrient requirements: N=high, P=high, K=high

Temperatures during the cold treatment should remain below 50� F (10� C) but above 35�F (2� C) for at least 250 continuous hours (about 10� days). Since it is difficult to prevent times when temperatures rise above 50� F (10� C) give the plant the cold treatment for an even longer period, let's say from four to six weeks.

Put the plants in a cold frame about six weeks before the last frost based on your location and zone. When all danger of frost is past and the soil temperature is above 60�F (16�C) set plants about 2 feet apart in the bed.

USDA Hardiness Zone -First Frost Date- Last Frost Date

Zone 1 -July 15th -June 15th
Zone 2 -August 15th- May 15th
Zone 3 -September 15th May 15th
Zone 4 -September 15th May 15th
Zone 5 -October 15th April 15th
Zone 6 -October 15th April 15th
Zone 7 -October 15th April 15th
Zone 8 -November 15th March 15th
Zone 9 -December 15th February 15th
Zone 10 -December 15th January 31st (sometimes earlier)
Zone 11 -No frost. No frost.