Planting Guide - Artichoke Seeds
How to Grow Artichokes
While the ideal growing conditions are cool and moist summers and mild winters, artichokes can actually be grown almost everywhere in the United States. Today, the majority of commercial artichoke production is found along coastal sections of Central California, where the weather is not too warm nor too cold. Castroville, California boasts the title of “Artichoke Capital”.
When & How to Plant Artichokes
In northern climates, it is best to begin your artichoke seeds indoors with heated mats so as to keep soil warm for 2 weeks until germination. Artichokes send down a long tap root, so be sure to start your seeds in tall pots to allow room for their root. Artichokes do not favor soil disturbances, so choose your pots wisely and only transplant once to their outdoor location, rather than several times to incrementally larger pots.
Begin seeding in February, water well but at no time should the soil be water logged or completely dried out. Keep indoors, maintaining a bottom heat of 75F. Begin the hardening off process after all threat of frost has passed. Gradually harden off artichokes for up to 2 weeks.
Growing Conditions for Artichokes
Artichokes grow best where there are mild winters and long, frost-free, moist summers. They will need at least 100 frost-free growing days. In areas with hot, dry summers provide afternoon shade.
Amend your soil with organic compost and keep it evenly moist, allowing soil to dry between watering. For zones 9-11, direct sow seeds ½” deep and thin to 6’ apart. Artichoke seedlings need lots of nutrients as they develop, feeding them once a week with a liquid plant fertilizer will be appreciated. Thin to their final spacing of 5-6' feet apart in warmer zones, while zones 6 and colder can plant their artichokes more closely, 2 to 3 feet apart, because frost will prevent the plant from reaching its mature, established size.
Keep soil moist throughout the growing season. Fertilize with a high-potassium liquid fertilizer every 2 weeks during periods of active growth to encourage flower buds to form. Keep beds weed free and use a thick layer of mulch. As buds form, remove mulch and apply a 4” thick layer of compost around each plant.
Each stem forms several flower buds, with the top bud ripening first. Harvest buds while they’re tight, firm and about the size of an apple before the buds begin to open. Cut stems about 1 ½” below the bud. Lower buds will mature later but won’t grow as large as the top bud.
After harvesting all buds, cut back leaving a third of the plant. On larger, established plants, cutting back may spur a fall harvest.
Preparing Artichokes for Next Season
Where winters are cold, cut plants back to 10” and cover with a box or basket, mulching with straw or leaves to help maintain an even soil temperature. Artichokes bear best the 2nd year and should be started from new plants every 3-5 years.