Growing Artichokes in Northern Climates

Growing Artichokes in Northern Climates

​Artichokes (Cynara cardunculus variety scolymus or Cynara Scolymus) are mostly grown in California, but anyone with approximately 100 frost-free days can grow them. On the central coast of California, artichokes grow as perennials, usually the Green Globe variety. But in other parts of the country, artichokes are grown as an annual plant. Here in central Wisconsin, zone 4b I grow the Imperial Star variety, which was specifically bred to produce artichokes the first year from seed, and most years I can get a great crop before our first frost hits.

Starting Artichokes from Seed

​Artichokes are one of the first plants I start, about 10 weeks before my average last frost date, although anytime between 8-12 weeks should work. The seeds are relatively large and tough and can take 3 weeks to germinate. They germinate best with a heat mat but if you have a warm room (70-80°F) a heat mat is not necessary. Artichokes have a taproot so if you start them in a small 6-cell tray you want to transplant them into a larger pot when they are still small. To get good flower bud production (the part you eat) they need 10 days of colder temperatures in the 40s while they are still seedlings. I move mine outdoors as soon as possible to achieve these temperatures but bring them in at night if it is going to dip below 40 and I have never had a problem with them forming buds.

Artichoke seedlings (large leaves) just about to get their first true leaves.

Growing Artichokes

​Transplant your seedlings after the danger of frost has passed or protect them from frost with a frost cover. They get very large, roughly 3 feet across, so plan on lots of room for them to grow. They also like very fertile soil, especially high levels of nitrogen. You can use compost, blood meal, composted manure, or fish emulsion. I try to fertilize monthly but if your soil is poor an application every 2 weeks may be better. Artichokes need plenty of water once they start producing flower buds. I keep my plants mulched with either leaves, cardboard, straw, or wood chips. This keeps moisture in the soil and reduces weed pressure. We also use drip tape throughout our garden to keep the soil moist without overwatering. Wood chips can reduce nitrogen levels at the soil surface or throughout the soil if you till them in at the end of the season. We have healthy soil and add compost and composted manure every year, so we see no decline in growth. However, we do not use wood chips around young seedlings with shallower root growth.

Harvesting

​When the flower buds are large, but the bracts are not fully open cut the artichokes off the plant at their base to harvest them. The main bud matures first, then several side buds mature later. You can allow some buds to fully flower; they turn into a beautiful purple flower that that bees love. The flower looks like a thistle flower which makes sense since the genus Cynara contains thistle-type plants.

Imperial Star artichoke flower.

Eating Artichokes

My favorite way to eat artichokes is to steam them for approximately 45 minutes. The smaller side shoot ones can be cooked for less time. Then remove the leaves individually and eat the fleshy base until you get to the center, the heart of the artichoke. The inedible, woody, spiny choke on top of the heart is removed and then the heart can be eaten. I like to eat the fleshy part of the leaves and the heart with garlic-herb goat cheese but there are lots of other ways to eat artichokes. 

Bees also seem to love artichoke flowers.

Conclusion

​I was very intimidated to grow artichokes for the first time as I, like many people, thought artichokes could not be grown in northern climates. However, artichokes are one of the easiest vegetables to grow in the garden. Once planted, they are low maintenance, and due to their spiky, thistle-like growth are deer and rabbit-resistant. I have also never had any insect damage, making them one of the easiest plants to grow.

Imperial Star artichoke.

References

1. Artichokes – Key Growing Information. Johnny’s Selected Seeds. https://www.johnnyseeds.com/growers-library/vegetables/artichokes/artichoke-key-growing-information.html
2. Cox, Jeff. 1988. How to Grow Vegetables Organically. Artichokes, p. 107-111. Rodale Press, Inc.
3. Smith, Richard, et al. Artichoke Production in California. 2008. University of California. Division of Agriculture and Natural Resources. http://anrcatalog.ucdavis.edu Publication 722.