Tree spinach (Chenopodium giganteum), also known as giant lamb's quarters or magenta tree spinach, is a fast-growing annual leafy plant belonging to the same family as beetroot, quinoa, and spinach. It is celebrated for its striking ornamental appearance — young leaves display vivid magenta or purplish tips that fade to deep green as the plant matures. Plants can reach up to 2 metres tall, making them one of the most dramatic edible plants you can grow in a kitchen garden.

The leaves are highly nutritious, providing good levels of vitamins A and C, protein, calcium, iron, and antioxidants. They have a mild, spinach-like flavour when cooked and are suitable for use in soups, stews, stir-fries, and as a steamed side vegetable. Raw leaves should not be eaten in large quantities, as they contain oxalic acid and saponins; light cooking neutralises these compounds.

Tree spinach is valued for its low-maintenance nature. It tolerates a range of soil types and is reasonably drought-tolerant once established. It self-seeds prolifically, which means a single planting can result in volunteers returning season after season. Its rapid growth and generous leaf yield make it an excellent choice for gardeners seeking a productive, space-efficient leafy green.

How To Grow

Growing Tree Spinach

Sowing

Sow seeds directly into the ground or start indoors in trays around 4–6 weeks before the last expected frost. Seeds are tiny — sow at a depth of about 0.5 cm and thin or transplant to 30 cm apart within the row, with 45 cm between rows. Germination typically occurs within 10–14 days at soil temperatures of 10–25°C. Tree spinach can also be sown in succession every 3–4 weeks for a continuous harvest.

Soil and Position

Choose a sunny or lightly shaded spot with well-drained soil. The plant tolerates poor soils but benefits from the addition of compost or well-rotted organic matter before planting. Aim for a neutral to slightly alkaline pH (6.5–7.5). Avoid heavy, waterlogged soils.

Watering

Water regularly after sowing and during establishment. Once plants are growing strongly, they are moderately drought-tolerant, but consistent moisture produces the best leaf quality. Deep watering once or twice a week in dry spells is usually sufficient.

Feeding

Tree spinach is not a heavy feeder. A single application of balanced general-purpose fertiliser or a top-dressing of compost at planting time is generally sufficient for the season. Avoid excessive nitrogen, which can lead to lush but weak growth.

Pruning and Height Management

Because plants can reach 2 metres, regular pinching out of the growing tips encourages bushier, more compact growth and increases harvestable leaf area. This also delays bolting. Stake plants in exposed or windy positions.

Self-Seeding

Tree spinach self-seeds very freely. Deadhead spent flower heads if you wish to prevent it spreading, or allow a few plants to set seed and natural volunteers will appear the following season.

Harvesting

Harvesting Tree Spinach

When to Start Harvesting

Plants are typically ready for a first light harvest 6–8 weeks after sowing, once they have reached at least 30–40 cm in height. For a more substantial harvest, allow plants to reach 60 cm or more. Begin harvesting young, tender leaves from the top of the plant, as these are the most flavourful and nutritious.

How to Harvest

Use your fingers or clean, sharp scissors to remove individual leaves or small stem tips. Always leave at least half the plant's foliage intact so it can continue growing vigorously. Harvesting the growing tips regularly encourages the plant to produce side shoots, greatly increasing overall yield.

Harvest every 1–2 weeks during the main growing season. The plant is resilient and regrows quickly in warm conditions.

Cooking Before Eating

Tree spinach leaves contain oxalic acid and saponins in their raw state. While small amounts of raw leaf are unlikely to cause harm, it is best practice to lightly cook or steam the leaves before eating to neutralise these compounds. Treat them exactly as you would spinach or chard — blanch, steam, sauté, or add to soups and stews.

Storage

Fresh leaves will keep in a sealed container or bag in the refrigerator for 3–5 days. For longer storage, blanch and freeze the leaves in portions. Dried leaves can also be powdered and added to smoothies or other dishes.

End of Season

As temperatures cool and day length shortens, the plant will bolt and set seed. Allow a few plants to go to seed if you want volunteers to self-sow the following season, or collect seeds for deliberate sowing.

Common Problems

Common Problems with Tree Spinach

Aphids

Soft-bodied aphids may cluster on young shoot tips and the undersides of leaves, causing distortion and weakening growth. Blast them off with a jet of water, or apply an insecticidal soap spray. Encouraging natural predators such as ladybirds and lacewings will help keep populations in check.

Leaf Miners

Leaf miner larvae tunnel through leaves, leaving pale, winding trails. Remove and destroy affected leaves promptly. Covering plants with fine insect mesh can prevent adults from laying eggs.

Bolting

Tree spinach is inclined to bolt (run to seed) quickly, especially in hot weather or when root-bound. Regular harvesting of growing tips delays bolting. Once a plant has bolted, leaf quality declines — remove it or allow it to set seed for next season.

Powdery Mildew

In hot, dry conditions with poor air circulation, powdery white mildew can develop on leaf surfaces. Avoid overhead watering in the evening, improve spacing to allow airflow, and remove affected leaves. A dilute solution of bicarbonate of soda in water can help manage mild outbreaks.

Overwatering and Root Rot

Tree spinach dislikes waterlogged conditions. Ensure soil is well-drained and do not overwater. Yellowing lower leaves and wilting despite moist soil can indicate root rot — improve drainage and reduce watering frequency.

Self-Seeding Invasiveness

Tree spinach sets seed prolifically and can spread widely if not managed. Deadhead flower heads before seeds mature if you want to prevent unwanted seedlings appearing throughout the garden the following year.