Jerusalem Artichokes (Sunchokes)



Tumbledown Farm’s Jerusalem Artichoke Page

Jerusalem Artichokes: Introduction

According to the New Whole Foods Encyclopedia "Jerusalem Artichokes are a superior source of inulin, a natural fructose that is medicinal for diabetics.  This sweet tuber relieves asthmatic conditions, treats constipation,....  [And is] an aphrodisiac...."

Tumbledown doesn't know about all that.  Sometimes I think people confuse inulin with insulin, though if sunchokes are substituted for potatoes you will remove a lot of starch from your diet.  The best thing is that Jerusalem Artichokes are easy to grow (native plants!), easy to store throughout the winter, and useful for all sorts of dishes from salads to chowders to roasts.  The rabbits will eat them too, tops and tubers, so that's another 40 lb bag of feed I'll not have to buy!

Never heard of a Jerusalem Artichoke?  Don't feel bad; neither had I until I read about them in John and Sally Seymour's The New Complete Book of Self-Sufficiency. (Or was it Farming for Self-Sufficiency: Independence on a Five-Acre Farm?  I forget now, but you can get either by following the links to Amazon.)  At any rate, the Seymours were nothing if not (how to say it nicely?) frugal.  If something of value could be had for little money or work, they could be counted on to know about it and be able to tell you how to do it yourself.  So that's how a "weed" came to be relished in my garden.

 I never dreamed I would find an "invasive" food plant!  Usually you have to improve the soil mightily to get a few puny vegetables to grow.  But not these sunchokes!  Go figure.  Just make sure you plant them in some "out of the way corner" where tall, weedy sunflowers will not get much notice.  If you are lucky, the only person in the neighborhood who will know that you are sitting on a pile of gold potatoes will be you!

 The neighborhood association may complain at your choice of flowers, but a Sunchoke is a flower!  You need not tell them that in a pinch Jerusalem Artichokes make good flour too.  That'll stay our little secret.

From Jerusalem Art...

People eat the Jerusalem Artichoke tubers, birds love the seeds (if the flowers are allowed to dry on the stalk), and livestock (like sheep; hence the name "lambchokes") will eat the whole plant.  Pigs will eat the plant and forage for the tubers.  (According to the Seymours, pigs are about the only animal that can clean out a field planted in sunchokes and make it ready for the next crop.)  I can attest that rabbits in particular will eat the leaves and stalk before they will eat the much tougher leaves and stalks of field corn or sweet corn, and will make short work of the roots (tubers) if they are washed free of the mud first.

From Jerusalem Art...

So, if Jerusalem Artichokes are so easy, how do you raise them in the garden?  Here's how I do it.  The first step, as usual, is to figure out what variety to sow and where to get them.  But before we get there, let's take a short look at the natural history of the plant.

Helianthus tuberosus

From Jerusalem Art...

Helianthus tuberosus L. (Asteraceae)

Part of the Asteraceae or Compositae (aster, sunflower) family, the Jerusalem Artichoke is a perennial herb that is native to North America and goes by many names: e.g., Sunchoke, Sunroot, Lambchoke, Topinambur, Girasol, Girasole, or Gerasole.

 There are many vegetatively propagated types, but no true (well-defined) cultivars.  Some of the most common types are:  'Fuseau', 'Jerusalem White', Veitch's Improved Long White', 'Sutton's New White', 'Mammoth French White' and 'French White Improved'. (Note: Fearing Burr, Jr. lists the Jerusalem Artichoke varieties available in 1865 as "Common White," "Purple-skinned," "Red-skinned," and "Yellow-skinned.")

The Jerusalem Artichoke is listed by the UN as a "famine food" and was eaten by Native American tribes.  For a full description and propagation information from the extension service, see the following Purdue Jerusalem Artichoke pages: Center for New Crops and Plants ProductsAlternative Field Crops Manual.

Where to buy Jerusalem Artichokes:

I bought my first Jerusalem Artichokes from Jung Seed and Nursery last year from their online catalog.  There is no indication in the catalog as to what type they are.  I purchased 3 lbs for $14.95 (+$5.00 shipping), but I see that the cost has gone up this year (2008) to $16.95.  At that rate, maybe I should sell a few tubers next year! (Note: I began selling home-grown Jerusalem Artichoke tubers for seed in 2009.)  For other nurseries that carry Jerusalem Artichokes, see the Tumbledown Farm Garden Resources page for links.

Planting Jerusalem Artichokes:

When to Plant Jerusalem Artichokes

Plant tubers (or fairly large pieces of tubers, the size of a golf ball or hen's egg or bigger, with three or more knobs or eyes) either in the fall or spring.  Plant them soon after you receive them from the nursery or seed catalog--or very soon after you dig them up yourself from a previous planting.  (Last year I planted with good results in very early spring.)  The usual advice applies to early spring plantings, do it "as soon as the ground can be worked." (But in central Indiana, you have to weigh that against waiting until May!) The books and guides will tell you to plant in fertile soil that has been dug or cultivated to a depth of 6"-8".  But I ask you, what "weed" needs such TLC?

 Sure, you'll get much bigger yields that way, but part of the fun of planting Jerusalem Artichokes is their "carefree" cultivation.  Why pamper a plant that will grow in almost any soil?  If it will grow in Alaska and Mexico--in rocks, sand, clay--and everywhere in between, and if it will grow in full sun or partial shade, dry or moist, why prepare a special bed, except to prove that you can grow more and larger sunchokes than your neighbor?  (Is your neighbor even growing sunchokes?)

From Jerusalem Art...

Last year I cultivated and amended the soil with peat moss and the like.  When the plants reach 12" high or so, I cultivated lightly with a hoe and mounded the dirt up around the stalks to provide extra stability later on.  (When the plant gets tall, it acts like a wind magnet and will get blown horizontal.  In high wind areas, you may even need to do some staking to keep them upright.)  

From Jerusalem Art...

This year I am experimenting with a different method for planting sunchokes.  I am using a bulb planter to take plugs out of the sod, dropping tubers into the hole at a depth of 4" and filling the hole with soil, topped with a layer of compost.  Later, when the plants are a foot high or so I'll begin to increase the depth of the mulch, smothering out the grass and other weeds.  Stay tuned, I'll let you know how the experiment progresses. (UPDATE 2009: This method worked very well and I recommend it for establishing new plantings. Pile the mulch 6-8 inches or higher as the plants grow so that larger tubers will form in the lower levels of the mulch at the conjunction of soil and new sheet compost. Compost or composted manure are also great "toppings" for this method of planting.)

If you are new to Jerusalem Artichokes, by all means you should prepare the ground sufficiently.  If you have other, less intensive, methods that have worked for you, let me know and I'll post them here.

The bottom line is that you plant sunchokes like you would plant potatoes.

Seeding Rate: How Many Sunchokes to Plant

Tubers are usually 2"-4" long and 1 1/2" in diameter.  The standard advice is to plant one tuber or partial tuber per foot (1' spacing).  If planting more than one row, make the rows three feet (3') apart.  That will be sufficient to allow the plants to shade the rows and keep the weeds out.  Last year I planted one row, approximately 12'-15' (with a few left over to plant in experimental spots) with the 3 lbs I purchased from Jung and--after a summer of severe drought--was rewarded with a 5 gallon bucket full of tubers when I dug on the first day of spring 2008.


From Jerusalem Art...

(I did not dig thoroughly, so I probably missed 1/3 to 1/2 of the tubers.)

Planting Depth for Jerusalem Artichokes

Standard advice, again, is to plant 4"-5" deep, in furrows.  (This year I am trying the "bulb planting" method outlined above.)

Remember, Sunchokes reach a height of 6'-10'.  They are big plants, so plant them where they'll not attract attention.

Harvesting Jerusalem Artichokes

Perhaps the best thing about Sunchokes in Indiana is that you can leave them in the ground over winter.  But you can begin harvesting as early as 16 weeks after planting.  Best thing is to begin digging a few of them up with a digging fork (spading fork, a shovel will be more likely to cut tubers in half and split them) as you need them in fall after the first heavy frosts and light freezes occur and you'll be able to eat them throughout the winter.  (Keep a mulch over them to make it easier to dig.)

 They are best preserved in the ground, so leave them there until you need them.  Their thin skin will cause them to shrivel if not kept moist.  You can dig them all up, as I did this year, on the first day of spring in order to make way for the next crop.  Or, if you planted them in an out of the way place, just let them multiply where they are.


From Jerusalem Art...

Some planting guides recommend cutting the tops to 5' high in late summer, but if you do that you sacrifice the flower.  Why take away the one beauty mark on an otherwise ugly plant?  (OK, if your only concern is yield and keeping the stalks from blowing over, sure, cut it back.)  If you wait until frost, cut the stems back nearly to ground level, but leave a short (4" or so) stalk to guide your digging later in winter and early spring.

Jerusalem Artichoke Pests and Diseases:

The only real problem you may have is how to keep it from spreading too far and wide!

Insects

There are very few insects that cause any problem with Sunchokes.  It is attacked by a variety of stalk borers, grubs, slugs, mites, and the like, but it is so hardy and fast growing that few pests can harm it significantly.

Diseases

White mold can cause early wilt and rot.  The best preventative and cure is a rotation with small grains or corn.  Downy mildew, rust and blight are also possible, but again the plant is so hardy (a "weed") that they usually are insignificant, not even reducing the yield of tubers by much.

Water and Temperature Requirements for Jerusalem Artichokes:

As already mentioned, Sunchokes grow wherever corn can be grown, and then some.  They are native to the central parts of North America (the U.S.)--sometimes even being viewed as a "weed" (an undesired plant out of place).  They require about 125 frost free days.  They can be grown in a wide variety of soils and do not require much in the way of pampering.  They thrive on 50" of precipitation per year and can make do with less.  They need moisture most in September-November, when tubers are being produced.  Jerusalem Artichokes do not like to be waterlogged.  If it gets extremely hot and dry they will also do less well, so some watering is useful in a very long drought (like summer 2007 in the Southeast and parts of the Midwest).  Optimum temperature is 65-80 degrees F.  They do not do as well in heavy, unamended clay, as they do in a good loam, but as the bucketful above makes clear, even in the heaviest clay they'll make do passably.  What else would you expect of a "weed"?  

Nutrients and pH:

Jerusalem Artichokes tolerate a wide range of pH (4.5-8.2), but do better in slightly alkaline soil.  (For that Tumbledown Farm at 7.9 is almost perfect.)  Those who use chemical fertilizers may want to use ( 4-8-4 or 4-12-4) at a rate that yields 1 1/2-2 oz per square yard of Nitrogen in annual replacement nutrients.  (Best bet in such cases is to get a soil test.)  If planted in rotation with a legume, there may be little need for fertilizer other than a little bone meal.

How to Cook Jerusalem Artichokes:

There are many Sunchoke recipes available on the web, so I'll not list a whole bunch of recipes here.  If you've never eaten a Jerusalem artichoke, suffice it to say that you cannot go far wrong by preparing it like you would a potato.  Sunchokes are more versatile than potatoes in that you can also eat them raw; slice a few like you would carrots for texture in a salad.  Add them to your favorite stir-fry recipe and you'll have a great substitute for water chestnuts.  The taste is not as bland as the taste of potatoes, so expect a slightly sweeter taste (think parsnips and turnips).  All that having been said, here's my favorite recipe so far (it's simple):

Roasted Sunchokes Recipe

2 lbs Jerusalem artichokes
Garlic Expressions (marinade)
Salt, pepper and other seasonings to taste

From Jerusalem Art...

1. Preheat the oven to 500 degrees.
2.  Peel Jerusalem artichokes and cut them into the size of large scallops or large 'tater tots (a little smaller than a golf ball).  Place in a single layer in the bottom of a large baking dish.  Drizzle with Garlic Expressions (or your favorite oil/garlic/vinegar marinade).  Toss until the Sunchokes are covered in the marinade.  Add other seasoning to taste.  (I like more fresh ground black pepper, sometimes a little dry oregano and the like.)
3.  Bake until tender, tossing every 10-15 minutes.

From Jerusalem Art...

This is a variation on one of the Sam Cooks Jerusalem artichoke recipes.

Jerusalem Artichoke Bibliography:

The American Horticultural Society, American Horticultural Society Encyclopedia of Gardening, "Jerusalem artichokes (Helianthus tuberosus), p. 351

Fearing Burr, Jr., The Field and Garden Vegetables of America, "Jerusalem Artichoke."

Purdue Extension Alternative Field Crops Manual, "Helianthus tuberosus L."  

Purdue Extension Handbook of Energy Crops, "Helianthus tuberosus L." (For large farming operations, but also yields some useful info for gardeners.)

Rodale's All-New Encyclopedia of Organic Gardening. "Jerusalem artichoke," p. 355.