New Zealand spinach is cultivated in gardens for its edible leaves, it is an excellent spinach substitute for hot dry weather conditions.

A perennial plant in its native habitat, but it is usually killed by the cold in British winters and so is grown as an annual. In the Tropics it is occasionally cultivated in the cool season as a spinach.

Easily grown in the garden, it prefers a light soil in a sunny position and thrives in dry soils. It grows best in a good rich soil. Once established, the plants tolerate drought. Plants are very tolerant of hot, dry conditions but cannot tolerate frost. Although very drought tolerant, the plants produce a better quality crop if they are given some water in dry weather.

Sow early to mid spring in a greenhouse. When they are large enough to handle, prick the seedlings out into individual pots and plant them out after the last expected frost.

Seed can also be sown in situ in late spring, though this will not generally make such good plants.

The seed can be slow to germinate, soaking in warm water for 24 hours prior to sowing may help.

Edible uses:
Leaves - raw or cooked. A spinach substitute, the shoot tips are harvested when about 8cm long, this encourages plenty of side growth with lots more shoots to harvest. A delicious substitute for spinach, the very young leaves and shoots can also be eaten raw in salads. The young leaves are best, older leaves developing an acrid taste.

http://practicalplants.org/wiki/Tetragonia_tetragonoides