Celery is a kitchen staple that you may (or may not) be able to grow in your home garden.
I say “may not” because it has thwarted me the few times I have tried it. Not that the plants didn’t grow, they grew quite well, through the cooler months, but they grew outward, rather than upward, and the flavor was very strong. Before we learn from what I did wrong, let’s learn the truth about this challenging crop.
A misrepresented edible
Celery plants have been misrepresented in elementary schools across the country for decades. The part we eat is not a stem, and the stringy bits that get caught in your teeth are not all plant veins. The familiar stalks, which are so well suited to dips and fillings, are actually the plant’s petioles, or leaf stems. Some of the differences between a stem and a petiole are:
Some of the indigestible strings of celery fame are vascular tissue, This is why, if you place a celery stalk in a glass of dyed water, you can see the dye move up, through the xylem. [Kids love this stuff!] The other stringy bits, however, are living structural components, called collenchyma. The tissues that make up the collenchyma are able to absorb water and behave much like a stiff gel, to hold the plant upright.
The celery plant
Celery (Apium graveolens) got its name from the Latin for ‘aromatic bee favorite’. As an umbellifer, celery is cousin to carrots, fennel, cumin, caraway, celeriac, parsnips, dill, parsley, anise, and poison hemlock. Celery flowers attract many pollinators and other beneficial insects, such as hoverflies. There are actually three different types of celery, each grown for a distinct crop: petioles, leaves, or roots. The celery plant originated in marshland - very unlike my hot, dry California summers, and only slightly moist winters.
How celery grows
Celery is a cool weather plant. It grows best when temperatures are 55 to 70°F. Grown in summer, it will bolt, or go to seed. This is fine, if you want to harvest celery seed for your spice cabinet. It is also a good way to end up with celery plants throughout your foodscape. Once a celery plant has gone to seed, the petioles will become very tough. [You can still use them to make soup stock, however.] Celery plants can tolerate light frost, but not consecutive frosts. Celery is a biennial, grown as an annual.
How to grow celery
While you can start a new celery plant from the base of a store bought celery, you need to be aware that those plants are certified safe to eat, but they are not certified safe to grow. Installing a store bought celery plant in your garden may be fine, and it may introduce a destructive virus or bacteria that may take years to overcome. It’s your call. Of course, you can always delegate those store bought celeries to indoor containers…
Celery is grown from seed. Seeds should be started 8 to 10 weeks before your area’s last frost date. You can also direct sow seeds in late summer for a winter crop. In either case, seeds should be planted 1/4-inch deep. Some growers recommend soaking seeds overnight prior to planting, to speed germination. Be sure to harden off your seedlings before planting them outside. Seedlings should be spaced 10 to 12 inches apart in the garden, containers, or raised beds, once they are 6 inches tall. If you have a particularly bright window, celery can be grown on a windowsill.
Celery needs lots of sun and it is a heavy feeder. You can protect and feed plants as they grow by top dressing around the plants with aged compost. Once petioles begin to emerge, you need to tie them together, to force them to grow upright. Celery needs least one inch of water a week to grow those crispy petioles. And they should be fed every 10 to 14 days. As the plants grow, gently build up soil around the plants, keeping the leaves exposed. This blanches, or etiolates, the stalks, by blocking light from reaching the chlorophyll, making them turn pale green to white. This also help prevent bitterness. You can get a similar effect by wrapping plants with straw, heavy fabric, or cardboard tubes, the same way you would with cardoons, to halt photosynthesis. Be cautious when watering, after you have set up your planting method. Water that sits on leaves and stems can lead to rot and other problems.
Celery pests and diseases
Celery is susceptible to aster yellows, bacterial leafspot, Phytophthora tentaculata, blights, mosaic virus, fusarium wilt, pink rot, and crater rot. Aphids, armyworms, earwigs, leafminers, lygus bugs, carrot rust flies, nematodes, whiteflies, treehoppers, cutworms, and voles will all take a bite out of your celery plants. You can sprinkle your celery plants with diatomaceous earth, to reduce many of the pests.
Like peanuts, celery is known to cause allergic reactions in some people. Contrary to popular wishful thinking, eating celery is not a 'negative calorie' experience. Digesting that celery stalk does not use up more energy than it provides.
Finally, did you know that celery flowers and leaves were used as garlands for King Tut’s tomb, some 3,300 years ago? I didn’t, either.
Umbellifers are aromatic plants with umbrella-shaped flowers.
Commonly referred to as the carrot, celery, or parsley family, Umbelliferae (or Apiaceae) plants are one of the largest families of flowering plants. Many of them are edible, and some of them can kill you. Edible or deadly, it is the flowers that make umbellifers easy to recognize.
Umbellifer flowers are called umbels. Umbels are clusters of simple or compound flowers that grow from a central point. The overall flower arrangement can be flat-topped or nearly spherical.
In addition to the flowers, umbellifers tend to share other characteristics. These include hollow, ribbed stems, divided leaves, long, sheathed petioles (leaf stems), and two-sided, flat seeds. There are exceptions.
Umbellifer plants: the bad guys
While all plants use a variety of chemicals in photosynthesis, reproduction, and growth, umbellifers produce another set of chemicals that can be aromatic (good) or toxic (bad). These chemicals are believed to be used by the plants as defense mechanisms. Here, in North America, we have two dangerous forms of umbellifer: poisonous hemlock and water hemlock.
Poisonous hemlock (Conium maculatum) is easy to identify, once you know what to look for. It has leaves that look like parsley, seeds that look like anise, and a root that looks like a parsnip. The telltale sign is purple or reddish young stems and older stems splotched or streaked with red or purple, usually on the lower half of the stem. This plant can kill you the same way it killed Socrates.
Water hemlock (Cicuta spp.) can also be fatal. In fact, water hemlock is the most poisonous plant in North America. According to the U.S. Forest service, “The leaflets of Cicuta can be distinguished from similar, non-toxic species in the parsley family (Apiaceae or Umbelliferae) by having veins that fork at their tips, with one branch ending at the tip of the leaflet and the other in the V-shaped sinus between adjacent leaflet lobes.”
These plants should be removed whenever they are found in the garden,
and be sure to wear protective clothing!
Umbellifer plants: the good guys
Umbellifers tend to be highly aromatic plants and many of them are a regular part of our diet:
Most umbellifers prefer cool weather, which makes them excellent late fall, winter, and early spring crops in San Jose, California. Planting in winter, and again in early autumn, can produce two crops a year. These seeds tend to be very tiny and should be planted 1/2-inch deep. Pests and diseases vary by species, so you will have to look up individual plants to learn more.
Benefits of umbellifers
In addition to being delicious and nutritious, umbellifers provide other benefits. Many pollinators and other beneficial insects are attracted to their flowers. Apparently, umbellifer flowers are easy to find, and they make easy landing and launching pads. Plus, they provide pollen, nectar, and a good hiding place, depending on which insect you are talking about. Many beneficial insects drink the nectar of umbellifer flowers, while their offspring, in larval form, feed on many common garden pests, including hornworms.
Which umbellifers are in your kitchen and garden?
Parsnips look like white carrots, well, because they are related!
Cousin to carrots, parsley, celery, and other umbels, parsnips (Pastinaca sativa) are native to Eurasia and have been cultivated since ancient times. In fact, parsnips were used as a sweetener before sugar cane made its way to Europe!
Parsnips are a cool weather crop in Mediterranean climates. Parsnips can be planted in September, and then again in February, March, and April in our region. If you live in a different area, simply check with your local Cooperative Extension Office for your best planting times.
Parsnip plant description
Parsnips leaves look almost like ferns, with pinnate (branched), toothed edges (margins). Parsnips are grown as annuals, but if you let a few of them go to seed, these biennials can start spreading edible roots in many areas of your foodscape. [Once they start that process, you won’t want to eat them - they get quite woody.] Second year plants can grow 5 feet tall, but your first year parsnip will be significantly shorter, at only 18 to 24 inches. Yellow, umbrella-shaped flowers grow into tiny ‘fruits’ called schizocarps. [How’s that for a fun garden word?]
How to grow parsnips
Parsnips, like other root crops, need loose soil. This makes them well suited to raised beds and container gardening. If you are planting parsnips in heavy clay soil, you will want to break up the soil down 18 inches and dig in 3 or 4 inches of aged compost. If you don’t, you will end up with forked and otherwise deformed roots prone to disease. Parsnip seeds should be planted 1/2 inch deep, with a heavy dose of patience. Parsnips seeds are slow to germinate and the plants take up to 4 months to reach harvestable size, but they are worth the wait! These sweet roots lend themselves to seasonings such as ginger and nutmeg, as well as more savory dishes, such as soups and stews. Parsnips can be grown in full sun or partial shade. They prefer slightly acidic soil, so you may need to make some pH adjustments. Seedlings should be thinned to stand 3 to 6 inches apart and be sure to eliminate all competition from weeds.
Parsnips pests and diseases
I had a difficult time tracking down parsnip pests and diseases on the West Coast. Other regions had plenty to say, but my guess is that that region is not conducive to growing parsnips commercially, so it gets less attention. Being more than a little determined, I am going to try growing them anyway!
It is my guess that, being a close cousin to carrots and parsley, parsnips will probably have many similar problems. These include armyworms, cabbage loopers, and aphids. Fusarium wilt, powdery mildew, bacterial leaf spot, and alternaria leaf blight may also occur. Other regions mention how celery fly larvae may tunnel into parsnip leaves, much like leaf miners. These pests can harm young plants, so remove infested leaves if you see them. I also found plenty of warnings about carrot flies. Carrot fly larvae are likely to attack parsnip roots, providing points of entry for canker and other fungal diseases. These pests are attracted to the smell of bruised plant tissue, so be gentle to your parsnips!
According to Wikipedia, parsnip canker is a real problem when growing this crop. Parsnip canker shows itself as orange-brown or black areas on the crown and shoulders. Also, the roots will crack. This condition is more likely to occur when seeds are planted in cold, wet ground that is too alkaline. It sounds, to me, that poor drainage is a parsnip’s worst enemy.
On the upside, many moth and butterfly larval forms use the flowers and undeveloped seeds of second year parsnips as a major food source. So, allowing a few parsnip plants to complete their lifecycle not only gives you free parsnip seeds and plants, it also adds biodiversity to your landscape and provides food for many beneficial insects!
Like many other root crops, parsnips taste sweeter after they’ve experienced a little frost. Since our ground is not likely to freeze, we don’t need to worry about getting our parsnip harvest out of the ground before it does. Other regions are not so lucky. Before you harvest your parsnips, however, be sure to wear gloves. Parsnips may be good sources of folic acid, potassium, fiber, and vitamins C and K, but they also have a powerful self-defense mechanism. Parsnip sap is toxic. If your skin is exposed to sunlight after handling parsnip leaves and stems, you are likely to get a rash. So, wear gloves.
Give these sweet root crops a try this winter and let us know what you think!
Furry carrots? Twisted roots? It might be aster yellows phytoplasma!
Aster yellows phytoplasma (AYP) is a disease transmitted by leafhoppers and root-knot nematodes. It gets its name from the family of plants affected (carrots and sunflowers), the symptoms (yellowing), and the bacteria that causes it (phytoplasma).
Aster yellows can affect all Aster family members, including celery, onions, coriander, caraway, and lettuce. Purple coneflower, marigolds, and coreopsis can also be infected.
Losses of 25 to 80% occur in commercial crops due to aster yellows. Quarantining new plants is the easiest way to prevent aster yellows from occurring in your garden or greenhouse. (I know it’s hard to wait ~ but some diseases never go away.)
The bacteria that cause this disease reproduce in leafhoppers, root-knot nematodes, and the phloem of susceptible plants. These bacteria help leafhoppers and nematodes live longer, but the opposite is true for our plants. As bacterial populations grow, they block the flow of sap, water, plant hormones, and nutrients within our plants, causing chlorosis (yellowing) and distortion.
Symptoms of phytoplasma infection
Stunted and twisting leaves are common symptoms of infection with aster yellows. Leaves can turn reddish-purple or yellow, leaflets may look more like scales than leaves, and flowers may look more like leaves (phyllody).
Flowers become severely distorted. Petals that should be white turn green (virescence), and the flowers themselves turn into leafy umbels (umbrella shapes). The root is significantly smaller, becomes woody, and sends out many lateral roots that make it look furry. Infected plants commonly send up clusters of dwarfed, deformed, chlorotic shoots called witches’-broom.
If you see these symptoms, pull the plant and throw it in the trash. You do not want this disease spreading through your garden or landscape via infected compost. Carrots infected with aster yellows are prone to soft rots and taste bad.
There is no known cure for aster yellows, so we have to look at the disease vectors: beet leafhoppers and root-knot nematodes. Since leafhoppers can overwinter in weeds and perennial ornamentals, such as thistle, dandelion, black-eyed Susan, and wild carrot, keep these plants trimmed back from carrot planting areas. It’s probably a good idea to plant your beets somewhere else, too.
Bacillus thuringiensis (Bt) can help control these disease carriers. If an area becomes infected, avoid planting carrots there for two or three seasons. Severe infestations require soil solarization, but that’s pretty drastic since it kills everything in the soil, including beneficial soil microbes.
If you have deformed carrots, I hope it is caused by rocks or compacted soil, as those problems are much easier to fix. And, hey, some of those carrots can look pretty amazing!
Some plants are out to kill you and hemlock is one of them.
Poison hemlock, also known as poison parsley and California fern, is not related to hemlock trees, but it does look an awful lot like a carrot gone to seed.
Poison hemlock (Conium maculatum) is a member of the Umbrelliferae (or Apiacea) family, making it cousin to parsley, celery, parsnip, dill, cumin, fennel, and carrot. All of these herbaceous, biennial plants have flower structures that look like flattened umbrellas. Native to Europe, poison hemlock was brought to the U.S. in the 1800s as an ornamental and is now found throughout the country. Whoops.
A deadly fern
All parts of the poison hemlock plant are extremely poisonous. In 399 B.C., Socrates was found guilty of heresy and corrupting the minds of Athenian youth. For this, he was sentenced to death by drinking poison hemlock. The alkaloids found within poison hemlock cause paralysis of several organs, including the respiratory system, usually within 2 or 3 hours. Eating only a tiny bit of the toxins found in poison hemlock can cause death. People with skin sensitivities may experience irritation by brushing against the plant, but eating it CAN kill you.
Poison hemlock identification
Poison hemlock looks a lot like both domestic and wild carrots, or Queen Anne’s Lace. Unlike Queen Anne’s Lace (Daucus carota) and domestic carrots, which have hairy stems and leaves, the leaves and stems of poison hemlock are smooth. Plants can reach 10 feet in height. The root, which looks a lot like a carrot, is pale yellow or white. It often smells like a mousy parsnip. Purple or red streaks or spots on slender, hollow stems is a clear sign that you are looking at poison hemlock. Stems may also have a white bloom that is easy to rub off. (Just be sure to wash your hands thoroughly afterwards!)
There are many branches and the plant often has a wispy, feathery appearance. Leaves are triangular and divided into many fractal iterations of the overall shape. Small, white, clustered flowers normally appear April through July. For comparison, carrot flowers tend to be more pink, but not always. Poison hemlock seeds are held within gray, ribbed fruit, in pairs.
Poison hemlock population explosion
Poison hemlock often grows alongside creeks and in locations with shade and moist soil. Many areas, including Cupertino’s McClellan Ranch Park and the Trukee River, see population booms after wet winters. Seeds (of many different plants) that had been dormant for several years use that moisture to germinate, rushing to reproduce. Just don't be fooled by this deadly plant's delicate appearance.
Just as the “leaves of three, let it be” rhyme has provided years of protection from poison ivy, try embedding this rhyme in your brain to help you stay away from poison hemlock:
Stems so smooth with purple streaks
Flowers white, a deadly stink
If you suspect poisoning from this plant, call Poison Control immediately at 1-800-222-1222. A quick response can save a life.
Thanks to John, curator at the Carrot Museum, I have learned that poison hemlock, for all its toxicity, is also used as a medicine. Seeds, roots, and leaves, when handled properly, can be used to treat respiratory conditions, such as whooping cough, asthma, and bronchitis. Poison hemlock has also been used to treat painful joints, to counteract anxiety and epilepsy, and to reverse strychnine poisoning.
Carrots are not just for bunnies!
Healthy, delicious, and more colorful than ever, you can grow carrots that are white, purple, red, and yellow, along with the familiar bright orange.
Carrots are related to fennel, celery, cilantro, dill, cumin, and parsley, all members of the Apiaceae or Umbelliferae family. These plants all have umbrella-shaped flower clusters that attract many beneficial insects. Carrots are biennial plants grown primarily for their taproots (the tops and seeds are edible, too).
How carrots grow
Carrot flowers change their gender as they develop. This means that a single umbel, or flower cluster, will contain both male and female umbellets at the same time, with the older female flowers on the outer edges, with male stamens closer to the center. After fertilization is complete, the umbel starts to curl upward, creating a bird nest shape. If allowed to grow through a winter and experience vernalization, your carrot plants will produce seeds for yet another crop. Selective harvesting can make your carrot patch a perennial food source.
Why grow carrots?
True to their ancestral home of modern day Iran and Afghanistan, carrots prefer growing in sandy soil. My heavy compacted clay is probably the worst soil for growing carrots. Plus, carrots are not exactly the most expensive produce in the grocery store. So, why bother? For the same reason we are compelled to grow our own tomatoes, peas, berries, potatoes, and more ~ it tastes better, we have more control over what goes into our food, and we reduce our carbon footprint.
Carrot body & color types
Carrot varieties are categorized by both color and shape. Carrots are classified as Eastern or Western, based primarily by color. Our common orange carrots are Western, while the more colorful yellow, purple, and crimson varieties are Eastern. Both Eastern and Western color types are then divided up by shape:
The shorter, stubbier, blocky shapes perform best in shallow soil (or containers), while the longer, slender growth carrots need more depth to grow well.
How to grow carrots
Carrots take 90 to 120 days to mature, depending on the variety. Carrots prefer full sun and cooler temperatures, but they can be grown in partial shade. While our clay soil is not the best thing for carrots, our alkaline pH is. Carrots prefer a pH range of 6.3 to 6.8. Carrots do not compete well with rocks and stones, so they are better suited in our area to raised beds. Carrot seeds are really tiny and can be difficult to space properly. One way to get around this is to stir together some carrot seeds, radish seeds, and some light soil or sand. Sprinkle this mixture over the planting area. The radishes will grow far more quickly than the carrots, creating automatic succession planting. It will also create space for the carrots. Once they emerge, carrot seedlings should initially be thinned to one inch apart. As you begin to see which plants are thriving, thin again to 4 inch spacing by cutting off the plants to be removed at soil level. This avoids disturbing the roots of remaining plants. Be sure to compost or dispose of these cuttings, rather than leaving them on the soil, to avoid attracting carrot pests.
Carrot pests & diseases
Being a root vegetable, most carrot pests are underground. Vegetable weevils, root knot nematodes, wireworms, flea beetles, and root maggots can damage your crop. Alternaria leaf blight has been known to wipe out entire crops. Being underground, these pests are generally not impacted by the use of pesticides. You can see a full list of common carrot pests and diseases on the UC IPM page on carrots.
- Carrots, combined with turnips, are in the Top Ten of important global vegetable crops, with 45% being grown in China. Only 3% of the world’s carrot and turnip production is domestic.
- Unwashed carrots can be stored for several months in layers of sand, or a 50/50 mix of sand and sawdust.
- Adding manure to carrot beds can cause split taproots.
- According to Wikipedia, “The roots contain high quantities of alpha- and beta-carotene, and are a good source of vitamin K and vitamin B6, but the belief that eating carrots improves night vision is a myth put forward by the British in World War II to mislead the enemy about their military capabilities.”
- This last one just a theory of my own. The Latin name for carrots is Daucus carota sativus. Daucus carota sounds an awful lot like ‘Doc’ and ‘carrot’ to me. Switch them around and I hear, “What’s up, Doc?” Coincidence? Maybe. But, maybe not…
Give carrots a try in your yard or on your balcony and let us know what you think in the comments section!
Once you plant this cousin to carrots, you will have a year-round food source. Fennel looks pretty in a landscape, too!
Large feathery fronds wave in the breeze, with yellow umbel-shaped flowers. The bulbous base looks like a rounded, closely packed celery. This perennial herb can grow quite large, up to 5 feet tall, depending on the variety. In colder climates, fennel is grown as a biennial.
Fennel as food
Milder than anise, all parts of the fennel plant are edible:
Fennel as medicine
Fennel (Foeniculum vulgare) also has medicinal uses. Fennel seeds contain volatile oils that stimulate mucus production in the digestive tract, providing temporary relief from digestive upset, Crohn’s disease, ulcerative colitis, Celiac disease, and irritable bowel syndrome. Fennel also reduces nausea and is said to ward off the effects of hangover (though I’m not sure about that one). In Medieval times, fennel was eaten as an appetite suppressant.
Fennel in the garden
Fennel attracts a wide variety of beneficial insects, including hoverflies, ladybugs, lacewings, bees, and syrphid flies. If larger varieties of fennel are selected, they make a nice landscape anchor.
How to grow fennel
Fennel can be started in San Jose, California, in spring or fall. It prefers sunny locations and is often seen growing wild alongside freeways. Fennel grows so easily from seed that wild fennel has become invasive in many areas. Seedlings should be placed 8 to 12 inches apart, depending on the variety. Young fennel plants require regular watering in summer, but I generally wait to water mature plants until they start to wilt without any noticeable ill effects. As the bulbs grow, bank a little dirt around them. This keeps them white and helps them to stay tender. When your fennel bulbs reach tennis ball size, use a sharp knife to cut away the roots, leaving them in the soil for beneficial soil microorganisms.
Fennel tends to bolt, or go to seed, when the roots are disturbed. This isn't necessarily a bad thing, as it will mean more new plants. If the roots are not overly disturbed, they will put out new bulbs. Viola! Perpetual food either way!
Find a sunny spot in your yard or use a large container to add fennel to your edible landscape!
Parsley - it’s not just for restaurants any more.
As a kid, I always turned a suspicious eye toward that sprig of greenery on my plate. My mother urged me to try it, so I did. Unfortunately, my young taste buds were not impressed. The mildly bitter bite of parsley was not my idea of delicious until many years later. Now that my taste buds are older and wiser, the refreshing tang of parsley adds a bright balance between flavors, cleanses the palette, and spices things up. If that weren’t reason enough to add parsley to a landscape, parsley packs one heck of a nutritional punch and, hey, it looks nice in the garden!
Parsley is a central Mediterranean plant. Parsley makes an excellent shade garden or container plant. You can even grow it on your kitchen window sill for easy access and nice color if you have strong enough sunlight.
Parsley is related to celeriac and celery, which explains its Latin name (Petroselinum crispum), which means ‘rock celery’, but it’s a heck of a lot easier to grow than celery. Parsley prefers well-drained soil that is kept moist, but my plants seem to grow under just about any conditions. Research has shown that parsley also repels asparagus beetles, making it a good companion to asparagus and tomato plants.
Growing parsley does require some patience if you are starting from seed. Seeds should be planted 1/2 inch deep, 6 inches apart, and they can take 4 to 6 weeks to germinate. Germination rates are pretty high, so growing parsley from seed is the most cost effective method. While you’re at it, plant some extras and give young plants to family and friends as gifts!
In tropical areas, flat-leafed and curly parsley are grown as annual herbs. In more temperate regions like ours, parsley is biennial. Biennial plants take two years to go from seed to seed, but some of my parsley plants keep on growing for another year or so. In addition to leaf parsley, there is a variety called Hamburg root parsley (P. crispum radicosum). Root parsley is grown for the taproot, which looks, cooks, and eats like a white carrot. (I may have to try that!)
Parsley plants allowed to go to seed provide habitat, pollen, and nectar to honey bees and many other beneficial insets, some swallowtail butterflies, and even goldfinches.You will probably also end up with many free, randomly placed parsley plants next year!
If flavor and looks weren’t reason enough to grow your own parsley, the CDC says it’s a nutritional gold mine. They ranked parsley at #8 as a food that reduces chronic diseases, such as cancer, coronary disease, and osteoporosis. To learn more, check out the U.S. Dept. of Agriculture’s nutritional analysis website that allows you to look up the nutritional value of pretty much any food. Just 10 sprigs of parsley provides 22% of the RDA for Vitamin C and 200% of Vitamin K.
It’s pretty. It’s durable. It’s good for you. And it tastes good.
Where’s your parsley planted?
Popular for its crisp, refreshing stalks, celery is a grocery staple in most homes. A specific variety of celery, however, is grown for its roots, rather than the stalks. This variety is called celeriac.
Also known as celery knob, celery root, knob celery, and turnip rooted celery, celeriac (Apium graveolens var. rapaceum) tastes like a cross between celery and parsley. (Celery, parsley, and celeriac are all members of the carrot family.) Botanically, celeriac is a biennial, but it is grown as an annual. Biennial plants generally live for two years, going to seed in the second year before dying. Celeriac is very popular in Europe, stores in the refrigerator for months, and is an excellent addition to soups, stews, salads and purées.
How to grow celeriac
Celeriac is easier to grow than celery, but it does have a tendency to bolt in hot weather. It grows best in in USDA growing zones 7 and higher. In our hot, dry region, celeriac is an excellent winter crop that is best started in late summer or early fall. Celeriac seeds are more likely to germinate if they are soaked overnight before planting. Seeds should be started indoors or in a protected area. Plant seeds no more than 1/8” deep and keep the soil moist until germination occurs by covering the soil with burlap, seed cloth, or vermiculite. Watering from the bottom of the container is preferable to avoid fungal problems. Germination should occur in 21 days.
When seedlings are 2-2 ½” tall, transplant them to a sunny location. Plants should be placed 6 to 24 inches apart. Celeriac is shallow-rooted, so use straw or other mulch around the plants to stabilize soil temperatures and reduce weed competition. The ancestor of celery and parsley was found in marshy areas, so keeping the soil moist and nutrient-rich with compost will improve crop size and flavor. Feeding young plants with fish emulsion every couple of weeks is an excellent way to make sure that they have all the nutrients they need. Lateral leaf shoots should be removed and the root shoulders should stay covered with soil to maintain tenderness.
The large root (hypocotyl) is usually harvested when it is baseball to softball size. Ideally, this is after a light frost, which converts some of the starch into sugar. Before eating celeriac, the brown outer husk is removed, similarly to jicama.
You can grow a surprising amount of food in your own yard. Ask me how!
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