Let’s talk about how to grow artichokes today! Whenever someone visits the garden, they always ask about the artichokes. Most people are surprised to find out that we can grow artichokes in our Zone 4 climate. However, with a few tricks, they can be grown in most climates. Keep reading to find out how to grow artichokes as annuals in your own garden.
Artichokes, oh how they make my heart sing. There’s hardly anything I love more than strolling down to the garden and picking one to eat as an appetizer. I’ll steam it while melting garlic butter with a fresh squeeze of lemon juice. Once steamed, I pluck off off a leaf, dip it in the butter, scrape it with my teeth, and wash it down with a crisp sauvignon blanc. It’s a transformative experience, indeed.
Globe artichoke is a member of the thistle family, in which the flower buds are edible before they bloom. You might be surprised that you can grow artichokes in most climates. The difference is whether you can grow them as perennials or annuals.
In Zones 7–11, you can grow artichokes as perennials, meaning they live more than two years. In Zones 3–6, you can still grow artichokes. However, you must grow them as annuals, meaning they complete their life cycles in a single growing season. This is completely OK, as most vegetables are annuals! In fact, there are specific varieties of globe artichokes for annual production, which we’ll talk about more below.
How to Grow Artichokes as Annuals
Since I live in Zone 4, I’ll be sharing how to grow artichokes as annuals. Because artichokes are perennial plants by nature, there are a few tricks to growing them successfully as annuals. By utilizing these tips, you’ll learn how to grow artichokes as annuals in no time 🙂
Selecting Seed Varieties
Choose artichoke varieties that are best suited for annual production. ‘Imperial Star’ is a green artichoke specifically bred for annual production that produces well-developed artichokes the first year from seed. ‘Colorado Star’ is also for annual production, but it produces purple buds.
Start Indoors
Sow artichokes indoors 8–12 weeks before last spring frost date. Click here to find your last spring frost date. Artichokes germinate best between 70–80°F. I put my pots under shop lights and place them on top of my Hydrofarm Seedling Heat Mat set to 75°F. Once seeds have four leaves, transplant to 4″ pots and grow at 60–70°F during the day and 50–60°F at night. The trick to growing artichokes as annuals is giving them a period of what’s referred to as vernalization.
Vernalization
Essentially, vernalization is the process of introducing plants to chilled temperatures in order to induce budding. For climates with mild winters, this happens naturally. Artichoke varieties like ‘Imperial Star’ and ‘Colorado Star’ require shorter periods of vernalization to produce buds. This why choosing the right variety is one of the steps for how to grow artichokes successfully as annuals.
These newer varieties require approximately 10 days of temperatures below 50°F (but above 32°F). The easiest way to accomplish this is by timing transplant so the plants can receive this exposure outdoors. Time transplanting so plants receive 10 days of 45–50°F. Protect from frost with blankets, cold frames, and so forth.
If this isn’t an option, start bringing the plants outdoors when temperatures are above 32°F. If freezing temperatures are expected, bring them into a porch or other protected area. However, do not bring them back into a warm house or greenhouse, as we are trying to trick them into a winter.
I’ve also read that you can simply chill seeds in the refrigerator for two weeks before starting your transplants. However, I have not tried this method.
This might all sound complicated, but I promise it’s not. Don’t stress it and do the best you can. I find these varieties to be quite forgiving.
Transplant Outdoors
Depending on vernalization period, transplant 6- to 12-week-old plants 2–3 feet apart in rows 4–6 feet apart. If your summers are hot, mulch plants thickly with straw to keep the soil cool. Artichokes are heavy feeders, so be sure to amend soil with organic fertilizer and top-dress with a layer compost. Once buds begin to form in July, I apply a high-concentrate liquid seaweed fertilizer. Artichokes have few pests other than aphids. Control aphids with high-pressure water spray or organic insecticidal soap.
Harvest
The first bud to mature will also be the largest, but the side shoots will also produce some respectably-sized buds. Clip mature buds before they open. Overmature buds can be tough and bitter, so it’s best to let them go to flower. They open up to mesmerizing lavender-colored flowers that attract all kinds of beneficial pollinators, so it’s a win either way. Buds can be stored for eating up to two weeks, but I prefer to eat them soon after picking. You can also freeze and/or can the hearts.
Alright, frand! Do you feel like you have a head start on how to grow artichokes? Let’s get you growing!
This is great information! I tried growing artichokes as an annual in zone 5 b, but hadn’t heard about selecting specific varieties or vernalization. When they didn’t flower we tried to over winter, in multiple thick layers of mulching but that didn’t work either. I will have to try growing as an annual again!
You have a beautiful website!
I’ve never been able to overwinter them either, but I’ve had great luck with ‘Imperial Star’ as an annual. I definitely think it’s worth a try! Thank you so much for your kind words 🙂
I purchased an imperial artichoke seedling from a store. I don’t know if it was vernalized. I’m in zone 7b. The plant is in a munched border next to my house/patio and is probably 18 inches tall by 18 wide. How large do they grow before the produce blooms?
Hi, Sue:
How exciting! A mature artichoke plant will eventually be about 3–4 feet tall and wide. I usually start to see a teeny tiny bud form right in the middle of the plant when it’s somewhere between 2–3 feet. Because it’s an imperial star, it will likely produce buds this first season if it received some cool temps. However, if it doesn’t, it will next year! Since you’re in Zone 7, you should be able to overwinter it and grow it as a perennial (lucky you! I have to grow them as annuals). It sounds like it’s doing perfectly fine, but you could add some balanced fertilizer to give it a boost. I also like to foliar feed with a liquid fertilizer high in phosphorous (linked in the article above) to encourage bud growth. Good luck and I’m excited for you to eat an artichoke you’ve grown 🙂 It also makes the most beautiful purple flowers!