Days to germination: 14 to 20 days
Days to harvest: 100 to 120 days
Light requirements: Full sun or partial shade
Water requirements: Very frequent watering needed
Soil: Very rich soil with compost
It’s not the easiest plant to grow, so take care to watch your plants carefully and be patient if you try to grow celery. You’ll need to be dedicated to watering your plants, but the sweet crunchy stalks at the end of the season are worth the effort.
There are a few varieties of celery, but very little real difference between them other than maturity times. Some will mature a bit faster than others. You can also plant varieties of celery bred to have fewer “strings” in the stalks which is ideal if you enjoy eating it raw. Golden Boy is one example of an almost stringless variety.
Don’t confuse celery with celeriac. They are closely related but are not the same plant. You use the large root with celeriac rather than the above-ground stalks like you do with celery.
Often eaten raw, celery is also cooked in a variety of dishes though not usually served on its own as a cooked vegetable. The water-filled stalks are also good candidates for juicing, and the leaves can be used to flavor dishes like soup.
Celery isn’t quite as nutrition-packed as some vegetables but you’ll get a good serving of vitamins K and C, fiber and potassium with every stalk. One of the great things about celery is that is has very few calories per ounce.
Starting from Seed
Celery’s long growing season makes it impractical to start your seeds outside in the garden, so you’ll either have to buy seedlings or start your own seeds indoors. Mark your calendar 12 weeks before your expected last frost date to start your seeds. Just the right time to start come broccoli too.
Celery seeds have a poor germination rate, so be generous with the seed when you plant. Plant at least twice as many seeds as you actually need. Don’t bury the seeds, just leave them on top of the potting soil or cover with just a sprinkling of earth. They need to be exposed to light in order to germinate.
Keep your seed pots warm, at least 70F and don’t expect any sprouting for 2 weeks or more. They need to be moist almost constantly. After they’ve germinated, you can let them get a little cooler (down to 60F). If you start them in seed pots, you’ll have to repot them into larger pots once they’ve developed a few leaves.
Though celery can usually stand a light frost or two, you should still plant your seedlings out into the garden at least a week after your last frost date.
Select a convenient spot in the garden that you can get at without too much difficulty. You’ll be watering almost every day, so make it easy on yourself. Your plants also need full sun but they will be fine if they get a bit of shade in the day.
Mix in a heavy dose of compost or other organic material, as well as lime into your garden soil. Plant your seedlings around 4 to 5 inches apart. To help keep the soil as moist as possible, add a heavy layer of mulch.
You have to make sure your celery’s soil stays moist pretty much constantly, which can easily mean daily watering. If your plants start to get dry, the stalks will toughen up quickly. When the hot weather of summer hits, even daily watering won’t be enough.
Celery needs a lot of nutrients, so fertilize once or even twice a month with a basic 10-10-10 fertilizer.
If you want the bottoms of your celery stalks to be pale, like you see in the supermarket, you’ll have to hill the soil up around the plant to blanch it (basically just block out the sun). You can use mulch if you prefer, which is a bit cleaner than dirt. Pile it a few inches up the stalks about a month before you intend to harvest the entire head. You can even tie some newspaper around the bottom to get the same effect. Some say that it takes out some bitterness but many gardeners don’t bother with it at all saying it really has no effect except for the color.
Celery have shallow roots and take quite well to containers. One plant per large pot works best. Since containers will dry out faster than garden soil, you will need to be particularly diligent about keeping your plants well-watered.
Pests and Diseases
Tiny chewed tunnels in your celery leaves usually means you have celery leaf miners. These tiny flies will only do serious damage if you have a large infestation of them, or your plants are still very small. Pick off any leaves with tunnels in them, and spray your plants with a natural pesticide.
If you see brown patches forming on your celery stalks, you probably have a problem with blight. Blight is a problem because it likes moist environments, just like your celery does. Its actually a fungus infection that can live in the soil, so rotate your celery to different parts of the garden each year. Fungicide sprays can help prevent it in the early stages. When you water your plants, keep the water on the soil not the stalks themselves.
A lack of calcium can turn the inner leaves of your celery black, which means you need more lime in your soil. There is little you can do once it happens, but next season add extra hydrated lime to your garden plot to keep it from happening again.
Harvest and Storage
You can start enjoying your celery before it completely matures by carefully snapping off the outside stalks once they are large enough. The plant will keep growing and will produce more celery this way.
Harvesting the entire head will most likely kill the plant but is a good idea once you know hot temperatures are coming. Slice through the stalks right near the soil level so that all the stalks stay joined together at the bottom.
Cut away the top leaves and you can use them for cooking. You can store whole heads like this in the fridge for a few weeks. It does not freeze well, so plan on using your harvest while its fresh.