Artichoke are Frost and Freeze Sensitive
Growing Artichokes / how to guide is primarily focused on high altitude gardening in the Park City Utah area. Artichoke pefers a sunny location and fertile, well drained soils. Incorporate plenty of organic matter into the area before planting. Start plants in late winter for early spring planting. Plant artichoke 18 inches apart in rows 2-3 feet wide. Fertilize the plants regularly with nitrogen and keep the soil moist throughout the summer. Control all pests that reduce vigor during the year. Harvest artichoke buds when they reach full size but before the bracts open. Plants are frost and freeze sensitive so they need to be protected. Imperial Star and Green Globe varieties perform well in Utah.
Recommended Varieties in Utah
Imperial Star - Medium sized plants, many dark green buds with small hearts. good disease resistance, excellent as an annual crop.
Green Globe - Large sized plants, many dark green buds with large hearts, do best if plants are maintained for several years.
Growing Artichokes / How To Guide
Soils
Artichoke prefers organic, rich, fertile soils for best growth.
Soil Preparation
Before planting, add 4-6 inches of compost and a complete fertilizer (16-16-8). Incorporate compost and fertilizer to a depth of 6 inches.
Plants
Purchase quality plants from local garden centers or seed catalogs if available. You may also grow artichoke transplants from seed. Germinate seeds at 70-75 degrees F, then plant in 2-3 inch pots. Start seeds in early January. Plants require 2-3 months to reach transplantable size.
Planting and Spacing
Artichoke should be planted 3-4 weeks before the frost-free date for your area. (Approximately June-1st in Park City Utah) Artichoke requires cool temperatures to initiate the flower stalk. If planted too late, plants will not flower. Space plants 18 inches apart in the row, with rows 2-3 feet apart. Planting through plastic mulches accelerates early growth and leads to higher yields. Water frequently after transplanting to ensure good root and shoot growth. Maintain healthy vigorous growth during the spring and summer to ensure that artichoke produces for a long time.
Water
Water frequently during the year. Use drip irrigation if possible. Mulch heavily around the plants to conserve soil moisture and reduce weed growth. Artichoke has a shallow root system, does not tolerate hot, dry conditions and likes moist soils if high productivity is expected.
Fertilization
Artichoke requires high amounts of nitrogen fertilizer for best growth and development. Apply nitrogen-based fertilizer (21-0-0) every 4 weeks beginning 4 weeks after transplanting to encourage sustained and rapid plant growth. Place the fertilzer to the side of the palnt and irrigate into the soil.
Harvesting
Artichoke harvest begins in late July or early August and continues until frost. Once the flower buds form, do not stress the plant. Harvest buds when they reach full size but before the bracts (bud leaves) begin to open. Cut off the bud with 2-3 inches of stem. Continue to water and feed the plants. Buds not harbested produce attractive purple blooms that cam be used as centerpieces or dried and used in flower arrangements.
Fall Plant Care
After the harvest is completed and the plant has recieved several frosts, cut back the leaves and dig up the plants and store tem in a cold cellar in moist sand or peat to keep the plant from drying out. Divide and replant the root the following spring.