Kale again in the "Dirty Dozen" - 2023

Each year, the Environmental Working Group (EWG) analyses the data from thousands of samples of fruits and vegetables tested by the United States Department of Agriculture for traces of pesticides (The 2023 guide includes data from 46,569 samples of 46 fruits and vegetables). From this they publish a report of the Dirty Dozen and the Clean Fifteen (the most contaminated and the least...).

Once again, strawberries top the Dirty Dozen list and kale is in the top three. Blueberries and green beans have been added to the list for the first time. The Dirty Dozen are fruits and vegetables that you should be especially careful to buy organically grown, or better yet, grow your own!

Here is a LINK to the EWG's full lists for 2023.

Here is a CNN article that summarizes EWG's work and contains other relevant links. LINK

Here is a link to the Sharing garden's post on "Why we eat and grow organic food".

And tips on growing kale in your own garden. 

Kale seeds, we saved ourselves...ready for planting!

No-Fail Kale: Growing Kale and Saving Seed

"The King of Vegetables; 'Kale' to the Chief!"

Cathy, Danielle and Llyn with "bouquets" of Red Russian kale to share at the Food Pantry.

Early spring in the Pacific NW is a time of joyful anticipation of the coming growing season. We already have hundreds of seedlings started in our greenhouses and, in a few short weeks we'll be able to transplant many early-season crops outdoors. But one of the great culinary pleasures of this time of year is the kale that wintered over from last season. Kale is one of those plants that when touched by a kiss of frost, becomes more sweet and tender than when growing at the height of summer.

Eat your kale for healthy skin, hair, bones and teeth!

There are many articles on-line about the nutritional benefits of kale and recipes for its preparation.  You will not find as many articles on-line about growing kale, using it as a cover crop, or saving your own seed which is what this article is focused on. (See also our post: Kale joins the "Dirty-Dozen' list: and How to Grow Your Own Kale)

But, before we get into growing kale and saving seeds, in researching this post I discovered two important facts: Kale has the densest concentration of nutrients, per calorie, of a wide range of foods tested. (PDF of 72 tested foods) (explanation of chart).

And secondly, it is extremely important that, the source of the kale you eat is organically grown.

"The health benefits of kale greatly depend on the source you buy it from. Whenever you shop for kale, make sure to get organic kale, as it’s one of the most heavily pesticide-sprayed crops. Two-thirds of produce sampled in recent evaluations were poisoned with pesticides and non-organic kale ranks among the world’s most heavily polluted crops."(source)

How to grow it: Kale won't grow well in the tropics or arid regions but it's perfectly suited to a moist, temperate climate such as the Willamette Valley of Oregon where we live. There are several varieties available. The main two we grow are Toscana (or dinosaur) kale and Winter Red/Russian kale. With its greyish-green leaves (without many frilly edges) and mild-flavored tenderness, Toscana is perfectly suited to make roasted kale chips (recipe below).

Toscana (or dinosaur) kale

But for ease of growing and hardiness through the winter, our favorite kale is Winter Red/Russian kale. This kale actually has the nickname 'hungry gap', after the period in winter in traditional agriculture when little else can be harvested. We've had stands of it survive, outside and unsheltered through the winter - through all but the most sustained snow and cold.

Toscana kale is darker green and its leaves are less frilly (far left). Red Winter kale, hardier and more vigorous (easier to grow through the winter) is on the right.

Sign, we put with kale at the Food Pantry as many people were unfamiliar with eating it.

Typically we grow two main crops of kale per year. The first we start in early/mid-February.  We either start them in pots/six packs and transplant them outside (late March/early April) or we start them directly in beds in the greenhouse. We pick from both these plantings all the way until mid-July when a) the leaves become bigger and less tender and b) there is so much else coming ripe that we prefer to eat! In the heat of summer they often also become infested with aphids and become inedible for this reason. This is then the perfect time to sow the second crop of the season (more on this below).

We start seeds in plastic tofu-containers with holes drilled in the bottom. We fill the containers mostly full of soil and press the soil down evenly with the bottom of another container. After sowing seeds, cover with scant, even layer of soil. Keep moist but don't over-water. These seedlings above are lettuce plants (to show spacing of seeds).

Once seedlings are large enough to handle easily and they have well-developed roots, but before they are root-bound, gently dump out the batch of seedlings and tease them apart, placing one in each cell of a six-pack.

In a few weeks, seedlings will grow and their roots fill the six-pack cells. They are then ready to transplant into garden-beds (18" apart). (Red Russian kale seedlings shown)

We have also sowed the seed loosely over a whole greenhouse bed in February (ideally the seeds are about 2" apart) and cover them lightly with topsoil. The kale comes up thickly filling the whole bed and grows rapidly in the protected climate of the greenhouse. It is easy to harvest whole clumps at a time with a sharp knife or scissors and, as long as you don't cut below where the leaves generate from, the kale will keep growing back all spring until a) you want to use the bed for something else or b) the greenhouse gets too warm for the cool-loving kale and it succumbs to aphids, or mold or gets too tough to enjoy.

Here, Chris is harvesting kale that was sown directly in a greenhouse bed. Using a sharp knife, he cuts off whole handfuls of kale leaving the node where new leaves sprout untouched for future harvests. The leaves will continue to re-grow for many, many months.

The second main crop of kale (for fall and winter eating) is sown in late July. It can be done in pots and transplanted, or loosely scattered as a thick crop (either inside or outside a greenhouse). It's counter-intuitive that you start these 'winter crops' in the peak of the summer heat but the seeds need enough time to germinate, and the leaves need long enough days to gain some height and volume as they will not gain much in size once the day-length shortens after autumn-equinox (Sept. 21 or so). We usually find it challenging to have enough room in our greenhouses at the peak of summer to grow a large kale crop indoors but, since kale does well outside, except in all but the harshest winters, we've had good luck with growing it outside.

Kale as a cover-crop: Below are some pictures of an experiment we did one year with kale as a cover crop. We sowed it thickly along with fava beans (tried to space plants about 2" apart). This was done by scattering the two varieties of seed and very lightly tilling them in with tiller at shallowest depth-setting. The kale did very well and lasted all through the winter. The fava beans succumbed to a sustained hard-frost and didn't survive till spring. After eating kale all winter-long, we tilled the rest in as a source for 'green manure'. This worked fine but we are now moving away from using the roto-tiller in the spring as it really compacts our clay-dense soil but, if you're still tilling in cover-crops and have a lot of kale-seed, it's a great way to go!

Kale and fava beans as a cover crop (planted in Sept., pictured in late October). Kale survived the winter; favas did not (froze). We ate kale all winter and tilled the kale into the soil in the spring as a 'green manure' (for fertility).

The same field of kale in February. OSU students harvesting a tub-full to take home and enjoy!

Springtime bonus: Kale 'raab'
Though there are some annual varieties of kale, most are biennial and set seed in their second season, after wintering over. If you have some kale that has survived the winter, look for the start of flowers forming. The best time to catch them is before the flowers begin to open (below). These kale flowers, called 'raab' (pronounced 'rob') are very tender and have a slight 'sweet' taste. They are loaded with vitamins and minerals.

Kale 'raab' (pronounced 'rob') is the flowers of the plant before they fully open. Tender, sweet and densely nutritious; a springtime treat! (pictured: Red Russian kale-raab) Note: Pick some leaves and stems along with the flowers; they'll still be tender at this time of year.

Here's Llyn picking raab off a Toscana kale plant in March or April.

Bella loves kale, raw from the garden! We prefer to steam it for about 7-min. and eat it with apple-cider vinegar or a splash of lemon-juice.

Saving seed: One of the pleasures of growing your own food from seeds is to begin to save your own seeds. With most varieties, it's not difficult and the seeds you save yourself will naturally select/adapt to be more perfectly suited to your local climate and conditions. It also contributes to having a greater sense of local food-security in case there ever comes a time when seeds are not distributed over long distances, or there is a seed-crop failure in another part of the country.

If left to mature, the raab opens up into yellow flowers. Once the flowers open, the plants become more woody and less pleasant to eat.

The flowers are pollinated and become seed-pods. Each plant can produce thousands of seeds! Wait to harvest the seed-pods till they are mostly turning purplish/tan and the pods are drying out (see above).

When ripe, the pods will easily open by rubbing them between your fingers yielding multiple seeds in each.

It's important to find the right time to harvest seed. You want to be sure the seeds are ripe enough that they are fully black and pop easily out of the pods, but don't wait so long that the birds eat your seed, or the pods shatter and spread the seed onto the ground below. Regardless of your best intentions, there are always some seeds that shatter out of the pods so you can anticipate 'volunteer' seedlings to germinate in places you've let kale plants go-to-seed.  We have one place in a greenhouse that has germinated kale plants for a third season in a row since we last let plants go to seed in that spot. That's what we call a 'high-quality problem'!

Mature kale seeds. Each plant is capable of producing thousands of seeds. This is just a small fraction of those saved from one plant.

You need to have some way of catching the seeds as the pods dry and open. After clipping the ripe seed-stalks, slip them gently in a paper-sack and hang in a dry place where birds and other animals can't reach them until the pods are all dry. You can also put them upside-down in a plastic tub or bucket. We have hung them from the rafters of our garden-shed, or on a shelf above our wood-stove, or put them in the greenhouse in a tub, on a shelf, covered by screens (to keep animals from eating them).

Seeds are ready for winnowing (separating seeds and chaff) when the pods are crisp and dry and crush easily by rubbing them between your hands. If it isn't in a tub already, carefully place the stalks of seed-heads into a tub and rub the pods between your hands to shatter them and release the seeds. As each stalk is cleaned, remove it from the tub. In the end you will have a mixture of seeds and dried leaves/pods (chaff). Winnowing is described in the caption below.

Here, Chris is giving a demonstration to Rook and Cindy of winnowing bean seeds (separating the seeds from the chaff). On a lightly breezy day, or in front of an electric fan, slowly pour seeds from one container into the other so the breeze blows the chaff away and the seeds fall into the lower container.

Storing seeds: Often, after winnowing, we continue to dry the seeds on a shelf above our woodstove. It is very important that they be totally dry or they can develop mold during storage. Heat can also destroy seeds so don't dry them any more than is necessary. Store seeds in a cool, dark place (or in your freezer, in an airtight container if you have the room). If you are new to saving seeds, check the plastic bags, jars or bottles a week or two after you store them to check there's no mold growing. We've lost a few batches due to mold which is always a sad thing when you go to check your seeds at the beginning of the next growing season.

Here's a LINK listing all our other posts about saving your own seed.

Delicious and nutritious, spring "greens": Toscana and Red Russian kale flanked by "Red Sails" lettuce.

Kale is easy to prepare and eat. We mainly use it steamed with a little apple-cider vinegar or lemon juice sprinkled on top, or a little butter but it it also good in smoothies (recipes), fresh in a tossed salad (recipe) or baked into chips (recipe). There are many great recipes on line. Always rinse well before using.

In the spring, when plants are small, the ribs will be tender and can be chopped right in with the rest of the leaves. As the plants mature, the ribs become more woody so best to slice them out and compost them.

Kale is incredibly nutritious. A 3.5 oz. serving (100g) gives you 7% of an adult's protein needs for the day as well as 5%- 15% of several vitamins and minerals. It is also very high in fiber.

(LINK: Health Benefits of Kale)

This 'ANDI' chart (below) lists 72 foods, rating them by their concentration of nutrients per calorie. Kale is #1! They're not suggesting that you rule out the foods that are higher in calories and less dense in nutrients (healthy bodies need high-quality fats, carbohydrates and protein) but most of us are deficient in the micro-nutrients (vitamins, minerals etc) and fiber, that are essential for all our metabolic processes and optimal health. (LINK: Aggregate Nutritional Density Index - note, kale is #1) (LINK to one-page, printable ANDI chart).

'Rob' with kale 'raab'

Here's another post we wrote about the health benefits of Kale:

Kale joins the "Dirty-Dozen' list: and How to Grow Your Own Kale 

 

The Sharing Gardens is a registered non-profit and tax-exempt organization. We exist entirely through donations. If you have found benefit from our project or our site, please consider making a small donation through PayPal. (Click button below.)

Do I Need to Buy Seed Potatoes or Can I Just Grow Potatoes from the Grocery Store?

Buying seed potatoes from a nursery catalog can be pretty pricey and its not really necessary. The only real advantages are that they sort them for uniformity of size (not a big deal), you know that they're ready for planting (see the discussion about dormancy below) and you can find some exotic varieties. We just use potatoes we saved from last year's harvest or buy them straight out of the produce section at the grocery store.   

The term "seed-potato" can be misleading. Potatoes do, on occasion produce seeds, but growers do not grow their crops from them. Instead, they grow them from small sprouting potatoes. Any potato, with sprouting eyes, that's at least the size of a chicken egg has the means to yield up to five pounds of fresh potatoes (Generally speaking, the smaller varieties of potatoes grow to maturity faster but yield less harvest.)

These green spheres in Chris' hand contain actual potato seeds but rarely do people grow potatoes from seeds

Potatoes are unique in that their growth cycle is not determined by length of day (as so many other plants are.) Potatoes have an internal clock that requires them to be dormant for a prescribed amount of time--different lengths for different varieties of potatoes. They won't sprout until their dormancy cycle has been reached. This is why some potatoes are better storage potatoes, because they won't start sprouting before you've eaten all the ones you want to eat.

When we want to plant more potatoes than we've saved from the previous year's harvest, we start looking for seed potatoes at the grocery store in late January (mid-winter in northern latitudes) and continue to buy them through till mid-spring. Many of the potatoes that have been in storage for the winter start to sprout in the warehouses at that time and you can get them for better prices. When selecting potatoes to plant, look for ones that already show signs of budding/sprouting from the eyes as this way you know they are viable for growing. Choose the variety you like best. Potatoes do not "cross pollinate". This means that, if you plant a russet, by golly you'll get a russet. (Note: one of our favorites is the Yukon Gold. They last a long time in winter storage and we like the flavor/texture too.)

Ideally, seed potatoes should be about the size of a chicken-egg. Larger potatoes can be cut and skinned over before planting. be sure you have at least three "eyes" per potato.

Potatoes need 70-90 days from planting to maturity so count backwards from your first frost date, or when you wish to begin eating your harvest! The exotic potatoes that come into the markets, and the small, egg-sized, common varieties are usually quite fresh; as they don't keep a long time in storage. They too won't be ready for planting till they naturally go through their dormancy cycle—four to six months. We haven't tried this but I read that you can hasten the dormancy by storing the potatoes in a cool, moist place for a few months and then putting them in a dryer, warmer (but still dark) area.

It is important that you buy organic potatoes because many of the commercially grown ones are sprayed with a "sprout-retardant" which gives them a longer shelf-life and this can delay their sprouting until the potato actually rots.

If the potatoes you have are only just starting to sprout and the buds aren't very long, keep them in the dark to encourage more sprouting. Once the buds are at least 3/4 of an inch long, it's time to "chit" them. 

How many to get? Each plant will take up about 12 - 16 inches of row space. If stored well, they will last for up to six months before starting to sprout again. Figure on 3-5 pounds of yield per potato you plant.  

What size should you get? Ideally you will find them that are about the size of a chicken's egg. Larger potatoes can be cut and allowed to skin over so they won't rot when you plant them.

What if they aren't already sprouting? If you can find potatoes that already have "eyes" that are budding, so much the better. This way you know they are viable for planting. As long as you buy organic potatoes (that have not been sprayed with sprout retardant), and allow 3-4 months time for them to begin to sprout, they do not already need to be sprouting.

When is it time to plant potatoes? Here in the S. Willamette Valley, unless you have raised beds, you need to wait to plant them till the ground dries out a bit. We planted them in early-April one year, when things were especially cool and wet and they just rotted in the ground. Depending on the variety you plant, they take 13 to 17 weeks to ripen. You may wish to plant them in succession so you'll have some potatoes to eat fresh and, the later harvests will last longer through the winter.

If you buy them in a plastic bag, transfer them into a cardboard box or paper sack so they don't rot before you get to them. Keep them in a cool, dark place, with good air circulation until they sprout. Layering them in a tub with leaves or straw, or sawdust works too. Just be sure to keep them from freezing.

Potatoes stored in damp layers of damp leaves. These had already begun to sprout and this storage protected their sprouts from breaking off, or the potatoes from drying out until we had the right conditions for planting.

Links to our other potato blogs, go to:

Sprouting Potatoes? What to do.

Can I Speed Up Potato Sprouting?

How to Plant Potatoes 

Planting Potatoes in Clay Soil

The Sharing Gardens is a registered non-profit and tax-exempt organization. We exist primarily through donations. If you have found benefit from our project or our site, please consider making a small donation through PayPal. (Click button below.)

Sprouting potatoes? What to do.

Why grow your own potatoes? Well for one thing, potatoes are one of those vegies that are good to eat organic and buying them organic can be expensive. They are a good use of garden space as a single plant can yield up to five pounds of potatoes. Also, they're fun to grow. This article will tell you how you can turn that scary tangle of sprouting potatoes under your sink, into a meal (or ten!).

Timing: Count backwards from when you wish to harvest your potatoes. Most varieties need between 17 and 19 weeks from planting to harvest. Add another two weeks for “chitting”. Chitting is a way to help the potatoes store up solar energy which makes them more likely to produce a big crop. Exposure to indirect sun hardens the sprouts so they are less likely to break. Also, the green in their skins is bitter and discourages pests from eating your seed potatoes in the ground.

This large potato was cut and allowed to dry on the exposed side before planting.

Sprout your potatoes: Potatoes must go through a natural dormancy before they can sprout again. This can be anywhere from four to six months. UNlike most crops, they are not sensitive to day-length but have an internal timing that can only be altered slightly to suit the farmer's planting cycles. If you wish to delay sprouting, keep potatoes in a cool, dry storage area. If you wish to hasten their sprouting, increase the temperature and moisture of their storage place. Layering them in damp leaves, in a tub kept in a heated part of your house will do the trick. The ideal sprout-length is about ¾ of an inch (10-15 mm). The longer they become, the more likely they are to break when you plant them.

If your potatoes have long, hairy sprouts: If your potatoes already have extensive sprouts, and the sturdy central sprout has many small root-hairs coming off the sides, it's important that you remove those, otherwise you'll get many tiny potatoes instead of a few large ones. These smaller side-sprouts also hasten the dehydration of the potato and weaken its ability to thrive. You can rub off the rootlets with your bare hands, they snap off easily. Multiple, thick sprouts are fine; just get rid of the fine hairs.

Potatoes on left ave too many rootlets. Ones on right have been stripped and are ready for planting.

Best size for seed potatoes: The optimal size for seed-potatoes is the size of a hen's egg. If you have larger potatoes, cut them so they have at least three “eyes” and sufficient flesh. Don't let the freshly-cut sides of potatoes touch each other as this may cause them to rot. (Some browning or blackening is normal for potatoes as they "skin over".) 
 

These are a good size for planting. Note the greenish hue from "chitting".

Chitting your potatoes: You can chit potatoes in your house near a window, or on a covered porch, or in a greenhouse (under a table). Don't put them in direct sunlight and, if there's danger of frost, cover them with a towel or cloth at night or bring them inside. After they have "greened up' a bit, and any cut parts have sealed over, they are ready to plant. 
 

Here are potatoes on a covered porch where they get indirect light.

Green potatoes are mildly poisonous so don't eat them after chitting.

If you have chitted your potatoes and its still too early to plant (the ground is too soggy or there's still snow on the ground) you can store them in a cardboard box or plastic tub, layered between leaves from last fall. You can also use straw. Or follow this link to an innovative way to extend the growing season of your potatoes. Link. We haven't tried this but it seems like it would work.

Some of our 2009 harvest, with seed potatoes stored in a paper sack (on the right).

How many potatoes should you plant? Depending on the variety, you can get five or more pounds of potatoes for each one you plant. You'll need about a foot between each plant in your garden and potatoes like lots of sun and loose, sandy soil. 

Links to our other potato blogs, go to:

Do I need to buy seed potatoes?

Can I Speed Up Potato Sprouting?

"Chitting" Potatoes
How to Plant Potatoes 
Planting Potatoes in Clay Soil

Spring has sprung! Sharing Gardens update

Hello friends and family of the Sharing Gardens - though we've had two brief snow storms since our last update, each accumulating about 2" of the white stuff, spring is definitely in the air! Temperatures are consistently reaching the low-to mid-50's in the day and rarely dipping much below freezing at night. Soon we'll turn the water back on to the garden spigots and give our two main greenhouses a thorough soaking, including the paths, and begin the cycle again of generating compost right in our paths! (LINK-How we grow...Veganic Community-based gardening)

Before we give you our latest garden-related links, you might enjoy watching this short video of a joyous, sweet song performed by the Masaka Kids Afrikana - I Look to You-LINK. Guaranteed to make you smile!

Early spring snow, soaking the ground.

In our planting zone (Willamette Valley, Oregon, USDA zone 7b), early March is a time of completing the pruning of fruit and nut trees and the pruning and care of other perennials (before warmer temps cause the sap to begin to rise). We continue to start seedlings both on heat-mats, and directly in the raised-beds in our greenhouses.

Though this picture was taken in 2022, it shows our 48 grape vines after pruning. LINK - Great video on Pruning Table Grapes.

Here are our most recent garden-related posts:

Growing your own celery is not difficult, it just takes a lot of time to get the celery plants started! (Their roots are very slow to develop). But once they do you can have cut-and-come-again celery that extends through the main growing season, and in a greenhouse, right through to mid-winter! LINK

Growing Lettuce from seed (with general tips about starting seedlings at home).

Great news for the Monarch butterflies in southern California! After a nerve-wrackingly low winter count of nesting Monarchs in 2021 (only 2,000), they seem to be bouncing back! (250,000 in 2022 and 335,479 in 2023). Even if you live too far north to help the Monarchs (there are no consistent sightings north of Portland Oregon), planting milkweed will still benefit other pollinators. They are gorgeous, stately plants and smell divine! Here's how to grow milkweeds: LINK.

Adri and Kaylynn holding up Showy Milkweed seedlings they helped grow.

In our last newsletter, we included a link to a video about a small town in NZ that came together during the lock-downs to collectively make sure all its members stayed fed with healthy food by, among other things, working as volunteers to create and maintain garden-plots for single-parent/low-income families. Any food that the families couldn't eat themselves was harvested and prepared into healthy meals at a small cafe/community-center. This hub of community also became the site for craft-projects and the sharing of practical life-skills such as sewing and simple carpentry to create useful products sold to raise money for the project to continue. 

We've received numerous appreciative comments for sharing the link. So, in case you missed the LINK in our last newsletter, here it is again.

And, in case this newsletter was forwarded by a friend, or you've just stumbled on our website for the first time and you would like to be added to our list to receive future newsletters, send us an email at the Sharing Gardens: shareinjoy AT gmail.com "Bee" well!  Chris and Llyn

How to Grow Your Own Celery

Though growing celery takes a little patience at first (the seeds are very slow to germinate), it is not a difficult plant to grow and the flavor and crispness of home-grown celery makes it well worth setting aside a little corner of ones garden for this delicious and health-enhancing plant.

This post covers:

• How to germinate the seed
• Transplanting/optimal soil conditions
• Watering
• "Cut and come again" - celery beyond the first cutting
• Nutritional content of celery and why to only eat it organically grown 

How to germinate the seed:  Most gardeners have a favorite way of germinating seeds but we'll just share what works for us and you can adapt it to your own preferences. 

Celery seed is very slow to germinate. Seeds can take 2-3 weeks to show their first leaves and the plants are not big enough to be planted in the ground for at least two months after that. Here in the Pacific NW, USA (USDA zone 7b) we start our celery in mid-February and they're usually ready to go into the ground by late April or early May. Don't worry if you've missed that planting schedule; celery can be started all through the spring. 

Celery seed is very slow  to germinate. Celery seedlings (left) over 1 month old. Lettuce (right) approx. 3 weeks old.

Our favorite variety that we grow is called "Utah". It's an heirloom/open-pollinated type so you can save your own seed. One plant will give you enough seed for years of future planting, plenty to use in cooking and to share with other gardeners.

One celery plant starting to flower. One celery plant will yield thousands of seeds!

For starting the seeds, we use tofu-containers with holes drilled in the bottom for drainage (see pic above), on heat mats in our greenhouse. We use a finely-sifted, well-draining potting mix that is not too rich. At this early stage, too much nitrogen can cause an algae-film to grow on the surface of your soil and lead to stem-rot in the plants. Moisten the soil before planting.

Being vegetarian, we eat a lot of tofu! With holes drilled in the bottom for drainage, they make excellent pots for germinating seeds.

Celery seeds are tiny and it can be a challenge not to sow them too thickly. Ideally you want about 1/4" between each seed. Put some seed in the palm of one hand and take a small pinch of seeds in the other hand. If you hold the seeds about 6" above your pot and drop them slowly, they will tend to spread out evenly as they fall. Use only the thinnest covering of finely sifted soil to lightly cover the seeds (or rinsed sand works too - be sure the sand you use doesn't have salts on it if you collected it yourself). Gently press the surface of the soil so the seeds below have good contact.

A good rule of thumb is to only cover seeds with soil twice as deep as the seed is thick. So, a millimeter-sized seed, would be planted approximately 2 mm's deep. 

They will germinate best with some bottom-heat from a heat mat, or to be kept indoors until the seedlings pop up above ground but as soon as the green leaves appear they need sunlight or a grow-lamp. Keep the soil moist (but don't over water!) by bottom-watering (in a shallow dish) or with a plant-mister as too much water can kill the tiny seedlings.

The seedlings will develop an extensive root-system first which can take many weeks. Don't give up on them! 

Transplanting/optimal soil conditions: Our celery seedlings go through two transplanting processes. First, once the root-system has developed and the plants are about 1/4 - 3/8" tall, we carefully tease them apart and give them each their own pot. Jumbo six-packs work fine. We have also used the tofu containers mentioned above (six to a container). These work well if you'll be able to do the next phase of transplanting as soon as the roots fill the soil. The jumbo six-packs extend this time a little bit as they hold more soil.

Transplanting tiny seedlings...

Celery is a heavy-feeder and the soil you transplant into should be well-draining and relatively high in nitrogen and minerals.

Allow the seedlings to grow for about two months or till they have a dense root system and healthy greens. (Celery pictured to the left still needs another month or so to grow. The roots are well-developed but they'll do better with more greens.) Our first transplants go into raised beds in our grow-tunnels (greenhouses) but a few weeks later, a second crop can be planted outside. Celery doesn't mind cool weather but it doesn't want a hard freeze, and, though you want to keep its soil moist, celery doesn't like soggy, wet feet (standing water).

Celery naturally grows flat on the ground (like a starfish - if seen from above). To get upright bunches (like you buy from a market) it must either be grown close together in a block, or in collars. In the first few years we grew celery, we used milk cartons and large soy-milk containers to keep the celery growing upright (see pics). The collars blocked the sun from getting to the celery and hence "blanched" it (kept it from getting too dark-green or tough). But we always had problems with slugs which found the collars to be a perfect habitat. For the last several years we've simply grown the celery close-enough together so each plant holds the others up that are around it. Spacing them about 8" apart seems to be the ideal distance. To use this method (without collars), plant them in a block or square (not a single row). They'll grow fine in a single row, they just won't grow upright and may be darker green and a little more fibrous.

We used to use milk cartons (held in place with bamboo stakes in two corners) to keep celery upright - it tends to flop flat - and to blanch it (direct sun makes celery darker green and more fibrous) but the collars proved to be ideal slug habitat.

Now we plant the celery in "blocks" (not rows), 8" apart, and the plants hold each other upright. They're not quite as blanched as with the collars but it takes less time and we don't have problems with slugs or snails.

Watering: Celery plants are approximately 95% water so they appreciate consistent, deep watering. In the beginning, after they're first transplanted in the ground, they'll need to be watered more frequently but not as deep. Later, it's better to water less frequently but more deeply which encourages the roots to reach down into the soil and pull up the water and minerals from below. Shallow watering creates a shallow root system which is much less tolerant to fluctuations in air-temperature and soil wetness.

Late winter celery in our greenhouse. This has been harvested once and grown again.

"Cut and come again" - celery beyond the first cutting: If you are careful about harvesting, celery will re-sprout from its roots. We cut just above the point at which all the stalks are still joined to the roots. The stalks will not be joined at the root (like you buy it in the store) but this gives the roots the best chance of re-sprouting. Keep the plant watered after harvesting to assist it in putting on new growth. This cut-and-come-again celery in the raised beds of our greenhouses has frequently survived through the winter, providing flavorful, mineral-rich stalks to harvest the following, early spring. Sometimes this second-growth celery is a bit more fibrous but it's still delicious and the fibers won't be a problem if you chop the celery finely.

Second-cutting of celery is often more coarse but also more flavorful. Chop finely to use in soups. "Mmm, good!"

The leaves of celery are typically removed before the bunches are sold in a market but they are delicious, chopped finely in soup or salads. They can also be dehydrated and used for seasoning for when you don't have access to the fresh plants.

Nutritional content of celery: Celery is high in water and fiber-content and very low in calories. Since celery is mostly made of water (almost 95%), it is not particularly high in any one vitamin or mineral. Nevertheless, celery is a good source of vitamin K, with one cup containing about 30% of the recommended daily intake, according to the University of Michigan. Celery can also help you get enough folate, potassium, fiber and the micronutrient molybdenum. It contains small amounts of vitamin C, vitamin A and some B vitamins. "Celery is naturally low in calories, carbohydrates, fat and cholesterol," (Read full post here: Celery: Health benefits & nutrition facts)

Always grow or buy organically grown celery. Having such a high water-content, it absorbs and retains pesticides and herbicides.

If you're not able to grow your own celery, always buy it organically grown. Because of its high-water content, it absorbs lots of whatever herbicides or pesticides that are used in growing it. It consistently shows up in the "Dirty Dozen" of fruits and veggies you should always buy from an organic source. (For more info, read this post: Which Fruits and Vegetables to Always Buy Organic-LINK)

As people tour our gardens, they commonly remark that they've never grown their own celery. We hope this post has helped demystify the process and we wish you much success with your growing.

 

And here's some more excellent guidance on growing celery from the National Gardening Association: How to Grow and Care for Celeries