Planting Artichokes [Soil, Location, And Sowing Seeds]
When to Plant Artichoke Seeds
Artichokes can be grown from seeds or shoots which are propagated from a mother artichoke plant.
If you live somewhere with mild winters where artichokes grow as perennials (Zones 7 through 11), you can plant them in late summer through mid-fall directly outside in your garden or yard. This will ensure the soil temperature is warm enough for the seeds to germinate and that it receives enough chill hours to produce buds in the spring.
If you live somewhere with shorter growing seasons and colder winters (Zones 3 through 6), it’s best to start seeds indoors using a heat mat. Start seeds in late winter or early spring and transplant them about 60 days later when temperatures are between 35 and 45 degrees Fahrenheit.
If you live in a climate where artichokes are grown as perennials, you can propagate shoots in late winter or early spring right before your last frost date.
For a complete guide on planning when to plant artichokes in your state and USDA zone, including required soil temperatures, read the article: When to Plant Artichokes.
Determine the Types of Artichoke to Plant
Here’s what artichoke seeds look like.
The next step is to determine which type of artichoke you should grow. There are six somewhat common varieties of artichokes to choose from depending on where you live.
If you live in Zones 7 through 11 where you can grow artichokes as perennials, your best choices are the Green Globe, Violetto, or the Emerald Artichoke.
If you live in Zones 3 through 6, you’re probably better off planting the Imperial Star variety. While slightly smaller in size compared to the Globe Artichoke, it matures early, produces many secondary buds, and is a hybrid designed for shorter and less-than-ideal growing conditions.
Other types of artichokes include the Big Heart and Purple of Romagna. The Big Heart is the largest variety of artichoke and the Purple of Romagna is an Italian heirloom favored by many chefs.
My favorite type of artichoke to grow in Southern California is the Improved Green Globe.
Can I Plant Different Varieties Together?
There is a risk of cross-pollination between different types of artichokes if you grow them together in the same space. I’ve personally not noticed any effect on the quality, taste, or reproductive nature of my plants due to cross-pollination.
I also don’t plant different types of artichokes next to one another, so there may be enough space to avoid this. I like to err on the side of caution, especially if you’re saving seeds.
Where to Plant Artichokes
Now that we know when we’re going to plant and what variety we’re going to plant, the next step is to find a suitable location. Site location is really important when planting artichokes because they can grow and produce for over 5 years. I’ve even heard of some having plants that are nearly 15 years old.
And you want them to keep producing because each year they produce more and more buds (the part that you eat). So think long-term if you’re planting them as perennials in Zones 7 through 11.
I grow my artichokes 4 ft apart along this fence for partial shade because I’m in a hot, dry climate.
How Much Space Do Artichokes Need
Artichokes can become quite large with some growing to be 8 feet wide and nearly 5 feet tall. So you’re going to need to give them plenty of space.
Whether you are planting them in a raised bed or directly in the ground, you want at least 4 feet in between each plant so they don’t overcrowd each other.
Because of how prolific these plants can grow, I don’t plant them in my raised beds. Instead, I plant them throughout my yard as edible landscaping.
How Much Sun Do Artichokes Need
Artichokes will grow in full sun or partial shade. For most places, it’s recommended they get at least 6 to 8 hours of direct sunlight. But if you live somewhere with hot, dry summers like I do in Southern California, I find that partial shade helps them grow.
Too much heat will cause them to flower early and you’ll lose the edible portion of the bud (or they won’t taste as good).
Protect Artichokes From Wind
Another consideration when selecting a location to grow artichokes is wind. If you live somewhere with a lot of wind, it’s best to stake your plants. Drive a stake into the soil a few inches from the center of the plant and use twine to tie it to the stake. This will give your plant extra support.
Another option is to put them close to a fence or something that will provide them with wind protection. We have strong Santa Ana winds where I live so I’ve chosen to grow mine close to a fence. This provides protection for them.
Planting Artichokes in Containers
You can grow artichokes in containers, but you’ll need a decent-sized pot to do so. Your container should be at least 24 inches in diameter and at least 18 inches deep.
Artichokes have deep root systems. The more space the roots have to grow, the more buds they will produce and the bigger the plant will grow.
Some options are half wine barrels, whisky barrels, or concrete pots. Make sure if you use a concrete pot that it has been properly leached for at least 3 days. If it is not leached, then it can cause the soil to become alkaline and artichokes don’t really like that.
Make sure the pot or container you use also has good drainage. If your plants sit in soggy soil, they will rot.
Are Artichokes Invasive
In climates where they grow as a perennial, artichokes are considered an invasive species. In large parts of California and Arizona organizations label them as invasive (California Invasive Plant Council).
If you live in these types of areas, it may be better to plant them in a pot. I personally do not. I plant mine in the ground and I have not had a problem with them so far. If you don’t want them to spread, be sure to harvest the buds before they flower and disperse seeds.
Artichoke Companion Plants
At this point, you’ve found a great location, selected which type of artichoke to grow and you know when you’re going to plant. Next, it’s best to choose which companion plants you want to plant with your artichokes.
While you don’t have to plant anything with them, companion plants can help with pollination and controlling pests.
Some of my favorite companion plants for artichokes include:
Peas (artichokes are heavy nitrogen feeders and peas return some nitrogen to the soil)
Queen Anne’s Lace (attracts predator insects that will spread to your artichokes and eat pests such as aphids)
Sunflowers (if you plant on the west side of your artichokes, they can provide shade which is important in dry, hot climates)
Tarragon (has a strong scent that repels some problem insects)
Thyme (acts as a ground cover to prevent moisture from escaping and if you plant it around your plant it will repel some pests)
Cabbage (requires similar soil and water conditions and will tolerate partial shade in the afternoon similar to artichokes)
Best Soil for Growing Artichokes
Artichokes are great because they’re not as picky about their soil as other vegetables. They will grow in sandy, sandy loam, and clay soils as long as they are well-draining.
We have heavy clay everywhere in our yard, and I plant my artichokes in it every year. One thing I learned was to observe your yard during rain storms and take note of any areas that flood or have trouble draining. You don’t want to plant in those spots.
Compost
When planting, you’ll want plenty of compost worked into your soil. In fact, I replace half of the soil with compost when I plant. The compost will also help the soil retain water if you have dry hot summers. I really don’t think you can add too much compost.
If you don’t have a composter, you can even bury your kitchen scraps 8 to 12 inches in the ground and put your soil on top. Within a few months the worms will do their work and those kitchen scraps will become excellent food for your new plant. I do it all the time.
Soil pH
Artichokes are fairly flexible but do well in slightly acidic soil with a pH between 6 and 8. You can send a soil sample to your local agricultural extension or buy a home soil test and do it yourself. I always use the Luster Leaf Rapitest. It comes with a nitrogen test as well (which I’ll talk about next). If you don’t have one, here’s a link to purchase one on Amazon. It’s super handy and I always have these on hand.
Nutrients
Artichokes are moderate feeders compared to other vegetables like pumpkins. The main thing you want to watch with artichokes is nitrogen. They need a decent amount of it.
I start by mixing in Espoma Organic Garden Tone which is a 10-10-10 when I plant. Depending on my nitrogen soil test, I may put less or more of this.
After that, I add 2 teaspoons of 21-0-0 ammonium sulfate every 4 weeks to sustain rapid plant growth. I side-dress it and irrigate it into the soil.
Many commercial growers use ammonium sulfate. It’s one of the best sources of nitrogen that I’ve found and will help your plants form proteins as well as photosynthesis. And in case you’re wondering (because I did when I first heard of it), the US Food and Drug Administration also recognizes it as safe.
While long-term use of this product in commercial growth can lower pH, I’ve never heard of it being an issue for home gardeners. We simply don’t use enough of it to over-apply long-term.
Watering Artichokes
Here is a circular drip line irrigation set up that I made from polytubing and a T connector. It’s all set up to an automed system.
Alright, we’ve got our site selected and the soil prepped and ready for planting. Now we need to discuss how we’re going to water these artichokes.
I personally think drip irrigation is the easiest way to water your artichokes. This will take some planning before you plant or sow seeds. If you currently have an irrigation system set up at your house, you can easily buy some 1/2-inch polytubing with 12-inch drips built in from Home Depot and create a ring like this around each of your plants.
If find this to be the best way to automate and ensure each plant gets enough water.
The other option you always have is to water them by hand with a garden hose or watering can. Just be sure that you water the soil and not the leaves to prevent diseases from occurring.
How Much Water Do I Use
If you’re sowing seeds, you only need to keep the ground moist for them to germinate.
If you’re planting transplants or shoots, water them deeply after planting.
Once they have a strong root system developed, artichokes are fairly drought tolerant, but you’ll want to give them extra water when flower buds are forming and during heat waves. A lack of water will result in fewer and smaller buds so keep the soil moist throughout the summer.
If you have a soil moisture meter, that is the best way to figure out a regular watering schedule for your plants. The soil should be moist at least 6 inches deep. Make sure it’s not soggy though. You don’t want to create a bog-like environment. Artichokes won’t survive in that kind of soil.
I typically water my artichokes two times a week when it’s hot and one time a week during the winter. Water them deeply and occasionally so they develop deep roots.
How to Plant Artichoke
Now that we’ve got everything set up, it’s time for the fun part - planting seeds (or shoots if you’re lucky to have some).
I soak my seeds overnight before planting them. I find that this improves my germination rate. I soak them in room-temperature water for about 12 hours.
To plant, place your seeds 1/8 to 1/4 inch in the ground. You don’t have to plant them as deep as other vegetables. Sow in groups of three and then thin to one once the seedlings are 2 to 3 inches tall.
The soil needs to be between 70 and 80 degrees in order for them to germinate. If you don’t have soil temperatures in this range, you may need to start them inside. Follow the same process, only grow them in a peat pot instead and make sure they have plenty of sunlight.
Provide them with light water immediately after planting and continue to mist or water when the top inch of soil is dry.
It’s also best to mulch around the plant afterward to help insulate the ground and prevent water evaporation. I typically use dried grass clippings from my lawn.
Planting Seeds Indoors
If you live somewhere with a cooler climate and you are growing artichokes as annuals, you’ll want to start your seeds indoors.
Start by stratifying them. You do this by wrapping the seeds in a damp paper towel and placing them in an air-tight container. Put that container in your refrigerator for about 2 weeks before planting. This process is very similar to when you grow a peach tree. It simulates winter conditions and tricks the seed into thinking it’s a different season.
After a couple of weeks, plant 3 to 4 seeds in a 4-inch biodegradable pot so that you can plant the entire thing in your garden later. This will prevent transplant shock and damage to the roots of the plant. You can fill your pots with any good potting mix.
Because of the manner in which peat is harvested, it’s not very environmentally friendly. While not a perfect substitute, you can also purchase these coconut fiber pots that are also biodegradable. I’m trying them out right now.
Use a spray bottle to mist the top of the soil daily. You want to ensure the soil stays moist, but not saturated. Place the pots on a heat mat or somewhere that can warm the soil to 70 to 80 degrees Fahrenheit.
Once your seedlings are 2 to 3 inches tall, thin them to one per pot. Some artichoke seeds may sprout stunted or albino due to genetic diversity. When thinning seeds, snip the seedlings you do not wish to keep as close to the soil level as possible.
Be patient, it can take up to 3 weeks for your seeds to sprout seedlings. You’ll grow them inside for up to 60 days and then transplant them outdoors 4 to 6 weeks before your last spring frost date. This will ensure you get enough chill hours for your plants to form buds.
It’s not advisable to transplant them directly but to harden them off first. To do this, you’ll want to set your seedlings outside for a few hours each day, slowly increasing the amount of time they spend outdoors each time. This will let them adapt to the change in temperatures and avoid shock.
Transplant them once your temperatures are above freezing, but below 50 degrees Fahrenheit to trigger vernalization (budding). Dig a hole two times the width of the pot and loosen the soil up at least 4 inches below where your biodegradable pot will sit. The crown of the plant should be level with the soil.
Congratulations! You’ve sown artichoke seeds indoors and planted them in your garden.
Planting Seeds Directly Outdoors
How to Plant Artichokes From Seed
I live in a mild climate in Zone 9. The temperature rarely drops below 30 degrees at night here. If you live somewhere similar, you can plant your artichoke seeds directly outdoors either in the fall or early spring.
Note that if you plant in the early spring, it may not bud until the second year.
Here’s my process for planting artichokes from seeds outdoors.
First I soak my seeds overnight for at least 12 hours. I find that this improves my germination rate.
Next, I till up my ground, digging a hole that is 8 inches deep and about 6 inches wide. I either backfill it with at least 50% compost or I simply bury a couple of inches of food scraps in the bottom. I have a very heavy, dense clay soil in my yard, so I find that loosening up the soil helps the plant develop a solid root system.
I plant my seeds directly in the soil, no more than 1/4 inch in the ground. Somewhere between 1/8 of an inch to 1/4 inch is good. I sow seeds 3 per location at a time and then thin the seedlings later to keep the best plant out of the three. Sometimes sprouts are stunted or albino so this increases the chances that I have a healthy artichoke plant.
After planting I give the soil a good soak and keep the soil moist. You don’t have to deep water every day, but I do lightly water frequently. Because I plant in the fall, the temperatures are usually a bit more mild here. I typically water every 2 to 3 days until the seeds germinate.
If we get a fall heat wave, I water daily. The important thing is to keep the top inch of soil moist in order for your seeds to germinate. If you plant them in a raised bed or container, you will most likely water daily because the soil will drain faster.
Be patient, it can take up to three weeks before you see any seedlings sprout. Continue to water regularly, keeping the top inch of soil moist.
Once your seedlings are 2-3 inches tall, thin them back to one per location.
That’s it! In a few months, you’ll have some delicious artichokes on your table.
Planting Shoots
If you’re lucky enough to have a friend or local nursery that sells artichoke pups (or shoots), you can plant those as well. If you have an artichoke plant in its second or third year of growth, you may notice shoots starting to grow around it. You can remove those and propagate them into a new plant.
If you’re using your own shoots from existing plants, the best time to divide them from the mother plant is in the spring after your last frost date. Try not to do it on a hot day with lots of sun. You’re going to have some transplant shock so this will help minimize it.
The easiest way is to use a hori hori knife, but you can use a hand trowel as well to separate the roots and shoot from the mother plant. If you don’t have a hori hori knife, I highly recommend one. You can buy one like mine at Gardner’s Supply.
To replant, dig a hole at least 8 inches deep to loosen the soil and replace about 5 inches with compost. Prepare the soil the same way you would if you were planting seeds. Do a nitrogen and pH test and amend accordingly.
Carefully place your shoot into the hole and fill the dirt around it. Water it deeply at the time of planting.
Mulching
Adding 4 inches of mulch after planting will conserve soil moisture and reduce weeds. Using organic material such as dry grass clippings or straw works great. If you use straw, make sure it doesn’t have a coating on it.
Once the buds form, remove the mulch and add 4 inches of compost in its place.
Be sure that the mulch doesn’t touch the stem of your plant. This can invite pests and diseases.
How Many Artichokes Should I Have
While there is no good answer to this, a plant that is cared for can produce up to 50 buds over its lifetime (California Artichoke Advisory Board). If you are growing artichokes for eating, I would suggest growing at least two plants to produce enough buds for eating each year. If you want to can them, I would grow more.
Germinating Artichoke Seeds
It can take up to 3 weeks for artichoke seeds to germinate. In order for germination to occur, keep the soil moist (not soggy) and the soil temperatures between 70 and 80 degrees Fahrenheit.
You can also stratify them by wrapping them in a damp paper towel, placing in an air-tight container, and refrigerating them for 2 weeks before planting.
Planting Artichokes Conclusion
For Zones, 3 through 6, grow as an annual and plant indoors in late winter or early spring.
For Zones 7 through 11, grow as a perennial and sow directly outdoors in early fall.
Plant in a location with full sun or partial shade if you live in a climate with hot, dry summers.
Artichokes produce buds for 5 years, so plan long-term. Space each plant at least 4 feet apart.
There are many types of artichokes. The Green Globe grows well in California and Mediterranean-type climates. The Imperial Star does well in non-Mediterranean climates.
Growing companion plants such as tarragon, thyme, peas, or Queen Anne’s Lace can help repel pests and improve your garden’s productivity.
Artichokes grow well in soils with pH between 6 and 8, and are pretty forgiving about soil type as long as it doesn’t become soggy when wet. You can plant in clay, loam, or even sandy soils.
Artichokes are medium feeders but require a good amount of nitrogen for rapid growth. If your soil is nitrogen deficient, feed them a 21-0-0 fertilizer when planting.
Plant artichoke seeds 1/8 to 1/4 of an inch into the soil. If you’re starting seeds indoors, grow in a biodegradable pot and transplant a few weeks before your last spring frost date.
Artichokes require chill hours to produce buds, so expose your artichoke to at least 200 hours of temperatures between 30 and 40 degrees Fahrenheit.
Seed can take up to 3 weeks to germinate in soil temperatures between 70 and 80 degrees Fahrenheit, so be patient.
Cole Sperry has built an extensive suburban garden at his home in Riverside, CA. He is a proponent of sustainability and reducing our carbon footprint, as well as eating closer to what nature intended. Today Cole can be found in his backyard garden experiementing with new gardening techniques and buidling garden memories with his children.