Stem Vegetables
Stem vegetables are plants whose edible parts are primarily their stalks or stems. These include asparagus, celery, rhubarb, and kohlrabi (though kohlrabi's edible part is a swollen stem base, sometimes classified with root vegetables).
Planting Stem Vegetables
Planting requirements vary significantly among stem vegetables. Asparagus is a perennial, while celery and kohlrabi are typically grown as annuals.
- Asparagus: Plant crowns in early spring in a well-prepared trench. It's a long-term crop, producing for 15-20 years.
- Celery: A cool-season crop that requires a long growing period. Often started indoors and transplanted. Needs consistently moist soil.
- Kohlrabi: Cool-season crop, can be direct-sown or transplanted for spring or fall harvest. Matures relatively quickly.
Common Stem Vegetable Varieties
Asparagus (Asparagus officinalis)
Varieties vary in spear thickness and color (green, purple). Choose disease-resistant crowns.
Celery (Apium graveolens var. dulce)
Look for varieties suited to your climate. Some are self-blanching, others may require mounding soil around stems for lighter color and milder flavor.
Kohlrabi (Brassica oleracea Gongylodes Group)
Comes in green and purple varieties. The swollen stem base is eaten raw or cooked, tasting somewhat like a mild turnip or broccoli stem.
Care and Maintenance
- Watering: Celery needs constant moisture. Asparagus needs regular water, especially when young. Kohlrabi needs consistent water for tender bulbs.
- Fertilizing: Asparagus benefits from annual applications of compost or balanced fertilizer. Celery is a heavy feeder.
- Weeding: Keep beds weed-free, especially for asparagus, as it's a perennial.
- Blanching (Celery): Some celery varieties benefit from blanching (excluding light from stems) to make them more tender and less bitter.
Harvesting
Asparagus: Do not harvest the first year. Harvest lightly the second year. In subsequent years, harvest spears when they are 6-10 inches tall by snapping or cutting at ground level. Stop harvesting when spear diameter decreases significantly, allowing ferns to grow and nourish roots for next year.
Celery: Harvest individual stalks as needed, or harvest the whole plant when it reaches desired size.
Kohlrabi: Harvest when the swollen stem base is 2-3 inches in diameter. Larger bulbs can become woody.