Vegetable
Carrot
Daucus carota subsp. sativus · Apiaceae
Also called: Garden Carrot
Carrot (Daucus carota subsp. sativus) is a moderate-water vegetable well suited to Tucson and the low desert. It's a moderate-growing vegetable.
Carrot at a glance
- Water use
- Moderate (established)
- Sun
- Full sun during the cool season.
- Mature size
- Tops 10-16 in. tall; roots 4-10 in. long depending on variety
- Growth rate
- Moderate
- Bloom
- White umbels (biennial; only flowers in its second year if left in ground — not desired for the root crop), Roots harvested winter to early spring in Tucson; flowers only if over-summered
- Cold hardiness
- Cool-season; frost-tolerant and sweetened by cold, with roots over-wintering well in Tucson soil. Heat is the limiting factor — harvest before summer heat causes bitterness.
- Soil
- Loose, deep, stone-free sandy loam is essential for straight roots; pH 6.0-6.8. Tucson's heavy or rocky soils cause forking — work soil deeply and remove rocks, or grow in raised beds/containers.
- Native range
- Cultivated form derived from wild carrot of Europe and southwestern Asia (Persia/Afghanistan region)
- Best used as
- Edible root, Storage cool-season crop, Containers and raised beds, Direct-sow garden staple
- Wildlife
- Foliage hosts black swallowtail butterfly larvae; flowers (if bolted) attract beneficial pollinators and predatory insects.
- Toxicity
- Edible and non-toxic to people and pets. (Foliage of the carrot family can cause mild skin sensitivity in some people; the wild relative is toxic but the cultivated root is safe.)
How to grow Carrot in Tucson & the low desert
Watering
Keep the seedbed constantly moist during the slow 1-3 week germination (cover with board or row cover to retain moisture), then water deeply and evenly to encourage long straight roots; inconsistent moisture causes splitting and forking. In Tucson direct-sow seed Sept through January for harvest before late-spring heat.
Fertilizer & nutrients
Light to moderate feeder; avoid high nitrogen and fresh manure (causes hairy, forked roots). Use a low-nitrogen, phosphorus/potassium-leaning fertilizer for good root development.
Pruning & care
No pruning; thin seedlings to about 2 in. apart so roots can size up. Harvest before the heat of late spring/summer, which turns roots bitter and woody.
Notes
Direct-sow only (carrots resent transplanting). In Tucson sow Sept through January; the long cool season lets roots size up and sweeten, but you must harvest before late-spring heat turns them bitter. Loose, deep, rock-free soil is the single biggest factor in straight, well-formed roots — raised beds are ideal in Tucson's rocky/clay soils.
Sources: University of Arizona Cooperative Extension – Pima County Monthly Gardening Guides (October, December); Tucson Organic Gardeners Planting Guide; Pima County Master Gardeners