Vegetable
Swiss Chard
Beta vulgaris subsp. vulgaris (Cicla Group) · Amaranthaceae (Chenopodiaceae)
Also called: Chard, Silverbeet, Leaf Beet, Rainbow Chard
Swiss Chard (Beta vulgaris subsp. vulgaris (Cicla Group)) is a moderate-water vegetable well suited to Tucson and the low desert. It's a fast-growing vegetable.
Swiss Chard at a glance
- Water use
- Moderate (established)
- Sun
- Full sun in the cool season; in Tucson it benefits from afternoon shade as temperatures climb in spring.
- Mature size
- 12-24 in. tall and 12-18 in. wide; colorful stems (white, gold, pink, red)
- Growth rate
- Fast
- Bloom
- Insignificant green; bolts to tall flower stalks if exposed to heat/long days (not desired), Harvest fall through spring in Tucson; bolts with spring heat
- Cold hardiness
- Frost-tolerant; survives light freezes to ~25-28 F with little damage, making it reliable through Tucson winters (USDA 9a-9b).
- Soil
- Rich, well-drained loam high in organic matter; pH 6.0-7.0. Amend Tucson's alkaline, low-organic soils with compost.
- Native range
- Mediterranean region and southern Europe (cultigen of wild sea beet)
- Best used as
- Edible leafy green (cooked like spinach), Edible colorful stems, Ornamental edible bed/container plant, Cool-season cut-and-come-again crop
- Wildlife
- Leaves can be browsed by rabbits and birds; flowers (if bolted) attract some pollinators.
- Toxicity
- Edible and safe for people. Like spinach it contains oxalates; large raw quantities are best avoided by those prone to kidney stones. No significant pet hazard, though oxalates can mildly affect pets if eaten in quantity.
How to grow Swiss Chard in Tucson & the low desert
Watering
Keep soil consistently moist; water deeply 2-3 times per week, more often in warm spells. In Tucson sow seed Sept-early Oct (and again Feb) for a long cool-season harvest; chard is one of the most heat-tolerant greens and can carry into early summer with afternoon shade and steady moisture.
Fertilizer & nutrients
Heavy feeder for leafy growth: work compost in before planting and side-dress with a nitrogen-rich fertilizer every 3-4 weeks during active growth.
Pruning & care
Harvest by cutting outer leaves about 2 in. above the crown; the central growing point keeps producing for cut-and-come-again harvest over months.
Notes
Excellent cool-season Tucson crop: sow late summer/fall (Sept-Oct) and late winter (Feb). More heat- and frost-tolerant than spinach, so it has the longest productive window of the common greens. Use afternoon shade and mulch to extend harvest into late spring.
Sources: University of Arizona Cooperative Extension – Pima County Monthly Gardening Guides (October, December); Tucson Organic Gardeners Planting Guide; Pima County Master Gardeners