Malabar Spinach

Sow seed a quarter inch deep in flats 6 to 8 weeks before your last frost. Before sowing, nick each seed coat with a file, sharp knife, or sandpaper and soak the seed in water overnight. Hold the flats at 65 to 75 degrees; germination still takes 10 days to three weeks. Basella has a tough, water-resistant seed coat, so untreated seed germinates slowly and unevenly. Scarifying and soaking open that coat and hasten germination. The seed also needs warmth: this crop cannot grow where temperatures stay consistently below 60 degrees.

Wait until two to three weeks past your last frost and the soil is 65 to 75 degrees, then set plants about 12 inches apart at the base of a sturdy trellis or fence. Do not rush this by the calendar; go by soil temperature. This is a tropical vine that is extremely vulnerable to frost and will not grow at all while nights stay below 60 degrees, so an early planting just sits and sulks or dies. It climbs to six feet or more and needs the support in place from the start.

On poor sandy soil only, work in nitrogen at roughly 80 lb per acre of actual N, with phosphate and potash at about 18 lb per acre each. Scale that to your bed size, and skip it on soil already high in organic matter. This is a leaf crop, so nitrogen drives the harvest directly, but Malabar spinach grows optimally in sandy loam already high in organic matter at pH 5.5 to 7.0, and the fertilizer only pays on thin sandy ground that cannot hold nutrients.

Irrigate regularly through the heat so the root zone never dries out. Do not let the plant coast between deep waterings the way you might with an established perennial. Dry soil is what triggers Malabar spinach to bolt into flower, and once it flowers the leaves go bitter and the harvest is effectively over. Continuous moisture is the single thing that keeps the leaves mild and succulent.

Check the foliage through the humid part of summer for fungal leaf spots caused by Cercospora beticola, and for snail damage. Remove and destroy infected leaves rather than composting them in place. Cercospora spreads from lesion to lesion on splashing water and wet foliage, so taking out the spotted leaves removes the spore source before it runs through the canopy. Malabar spinach carries flavonoid glycosides that make it resistant to tobacco cutworm, so it rarely needs insecticide at all.

From about 70 days after sowing, hand harvest by trimming young leaves and the tender young stems. Prune overlong vines and pinch the tips as you go to keep the plant in shape. Hold picked leaves at 50 to 60 degrees, where they keep 12 to 14 days. The young leaves and shoot tips are the tender, edible part, and this vine twines and rambles hard enough that it needs periodic cutting back of overlong vines just to stay manageable on its trellis. Keep the soil moist while you pick: it is dry soil, not the picking, that pushes the plant into bloom and turns the leaves bitter.

Ahead of your first frost, cut stem tips and root them in water or moist soil, then keep them indoors through winter. Outdoors it survives the winter only in zone 10 and warmer. Frost kills this vine outright, but the stems root readily wherever they touch moist soil, so a tip cutting is a far more reliable way to keep a favorite plant than saving seed with its stubborn seed coat.