Artichoke

Artichokes are Mediterranean plants that thrive in full, hot sun. They need a minimum of six hours of direct sun every day during the peak of summer. A rich, well‐drained soil is ideal.

In the Portland area, seeds can be started inside from February through April (two months before the average last frost date), and directly outside starting in May. If starting inside, plants should be transplanted in late spring, when the ground has warmed and there is no chance of frost.

Ideally, plants should be placed 3 feet apart in a site protected from winter winds and extreme cold. Amend soil with 2” of compost and/or manure before planting. Add an organic transplanting fertilizer to the bottom of the hole. Once planted, top‐dress with good mulch, making sure not to smother the crown.

Artichokes like moist, but never soggy soil. When watering, drench the root area completely.

Frequency of watering varies with every situation. In the heat of summer, it may need a thorough drink once a week. Watering frequency will decrease during cooler weather and as plants become established.

Artichokes are very drought tolerant once established after the first year. Water a second-year plant thoroughly in the hottest summer months. A third-year plant should be fine without additional water.

Container grown artichokes will need regular, weekly watering before the soil pulls away from the sides of the container. Container grown artichokes will have a restricted root system, so they’ll need regular water for life.

Artichokes benefit from an annual feeding in the spring. Side‐dress with kelp meal or any other all purpose granular fertilizer. Adding a 1” layer of composted manure will also work well.

Newly planted artichokes begin to produce edible heads early to mid summer. Established plants can start flowering in late spring. Harvest before the outer “petals” have begun to open, and be sure to cut buds with 1” of stem along with it. Store in the refrigerator and they’ll last up to a week or more.

Snails and slugs leave large holes in leaves when they feed at night. Slug baits and beer traps are just a few ways to control them.

Verticillium and Bacterial Wilt are soil borne viruses which cause the plant to suddenly wilt. Remove and destroy infected plants. Replant a new plant in a different area (or container).

All artichokes have a limited life span and lose vigor, dying away after 5 years of production.

Gray mold shows as brown spots on buds, and they will eventually develop a white or gray mold in wet weather. 

To treat the plant, remove infected buds, avoid overhead irrigation, and improve air circulation. Treat healthy foliage with a fungicide if desired.

Aphids often appear as a black coating on the flower buds. You’ll also see sticky sap on leaves or stems, and white aphid skeletons will be quite prevalent. There are numerous sprays and control measures to help combat aphids. Artichoke and cayenne sprays help deter them, and insecticidal soap kills them when spayed every 7‐10 days.

Earwig damage appears as holes bored through the base of the buds. Set traps made out of rolls of corrugated cardboard. Earwigs will hide in the cardboard during the day. In the morning shake the traps into a bucket of soapy water, or simply discard away from the garden.

Cut artichoke foliage to the ground in late fall. Container grown artichokes need protection at temperatures around 25°F or colder. When planted in the ground, adding a thick layer of straw will help insulate the root mass for the winter.

The key for survival in the ground is great drainage and temperatures above 20°F.