Soil Type and Preparation
Celery is not that commonly grown in home gardens because it is readily available from your grocery store and it is rather difficult to grow it compared to other vegetables. It needs much water, cool temperatures, and requires a long growing season, but when you finally hold the tender stalks in your hands, the taste multiplied because of all your care, you will know that it was all worth it.
If you want to grow celery in your garden, make sure you have the correct soil type for this. The soil should be rich with a pH of about 6.0 to 6.5 and can be made rich by hoeing plenty of compost and manure into the place where you want to plant the celery. Sprinkling the gardening site also enriches its potassium level, which is critical for the celery.
Indoor Seedling Growth
The seedlings should be started inside since the celery has such a long growing season (120 to 140 days) about two months before you expect the last frost in your area. Since the seeds are very small, it will be helpful to mix some of the earth in with the seeds, and then sow the seed/earth into your small pots.
After a week you will be able to thin the seeds to about 2cm apart and make sure they have enough sun, water, and nutrients. As the seeds grow larger, make sure there is only one seed per 10 cm, and choose the largest celery, which will help you gain a hearty harvest with only the strongest plants.
Transplanting the Seedlings
When you are sure there is no more chance of frost, you can start hardening off the seedlings by leaving them outside during the day and bringing them back inside at night until the night temperature is steadily above 50 degrees Fahrenheit. This hardening off process will likely take about 15 to 20 days.
Now you will be able to transplant the seeds. Just before planting work some general-purpose fertilizer into the soil. Plant them about 20 cm – 30 cm apart and slightly deeper then they were in their pots before. Water the seedlings with some fertilizer if you like, but do make sure that the plants have plenty of compost and mulch around them to help them retain more water.
Care until Harvest
Until the growing season, keep watering the celery to keep it moist, and periodically add more mulch for both nutrients and its water-retaining abilities. The celery will also benefit from some general fertilizer mixed into the water once a month. When the plants reach a height of about a foot or more, it is time to harvest the celery.
Usually, the outside stalks are very dirty and tough, so it would help if you discarded those. You could also use them in your compost to help your next celery batch next year! Of course, you can just harvest as many stalks as you want, or you can pull out the whole plant by pulling up the root. Enjoy your homegrown celery!