Perpetual Spinach is not spinach, nor is it perpetual, but it does grow reliably for quite a long time in the garden!
This old heirloom is, in fact a relative of chard. You rarely see it in the shops because it ideally needs to be picked soon before eating. The leaves are shiny green with white midribs. The steamed stalks taste something like mild asparagus.

'Perpetual Spinach Leaf Beet' also known as 'Spinach Beet' Chard, responds particularly well to repeat cutting and is one of the easiest and most productive vegetables for a small space. It is bred to have minimal stem and maximum leaf production and will grow to 50cm (20in) in the first year.

Perpetual Spinach is extremely resistant to bolting, so with just one sowing you can feast on these succulent dark green leaves and white stalks the entire summer and through autumn and winter.
Use raw in salads, steamed with other greens or in place of spinach. Include in quiche or lasagne for a savory change of pace.

Position:
You can grow Perpetual Spinach in most parts of the garden as long as it is not in deep shade but will give a better yield when in a sunny spot. While this plant is very forgiving and will grow where the soil is the poorest, like any plant this prolific grower will respond to compost, manures and fertilizers. They require a good draining soil.
One planting will almost always last the season, so plan a permanent place for it. Perpetual Spinach grows well in a soil of around 6.5 to 6.8 pH. An acidic soil will stunt growth. It is resistant to most plant diseases but seedlings will need protection from slugs.

Sowing: Sow in spring, alternatively sow in autumn to overwinter

Sowing Indoors: Sowing early.
Perpetual Spinach is normally sown directly into the soil, but for an early crop, a few seedlings can be started indoors. Transplant them outdoors when the night temperatures are at a minimun of -2°C (28°F). It will sprout fairly early, and will not be harmed by spring frosts.

Sowing Direct: Sow in Spring as soon as the soil can be worked
Sow the seed thinly 5cm (2in) apart at a depth of 1cm (½in). If growing more than one row, space the rows about 38 to 45cm (15 to 18in) apart. The seedlings will appear in about 15 days and should be watered for the first month or so if conditions are dry.
The plants will need thinning to about 15 to 25cm (6 to 10in) between plants. If left until around 15cm (6in) in height before thinning then the thinned plants can be treated like an early harvest and the young leaves will be extremely tender and tasty.

Sowing in Containers:
Pick a good-sized container around 45cm (18in) wide and 45cm (18in) deep. Fill it with compost and sow your seeds as you would do in a vegetable plot. Aim to end up with around four plants in a container this size.

Cultivation:
Perpetual Spinach is a hardy vegetable and will grow with little or no attention.
Their main need is for weeding. This can be done by regular hoeing. An alternative is lay black plastic and let the plants grow through this. Black plastic is particularly useful because they stay in the ground for so long.
Perpetual Spinach is sturdier than spinach and can cope better with water shortages, however you should still water regularly to ensure optimum growth and prevent bolting. Bolting leads to premature flower and seed production and will divert the plants energies away from leaf growth. If a flower stalk develops then clip it off to extend the harvest.
To extend harvesting past the first hard frost you can put the plants under a cloche or polytunnel to extend the growing season.

Harvesting: Approx 50 days to maturity.
Perpetual Spinach can be picked as soon as the leaves are large enough to harvest, usually in four to six weeks. The best leaves for salads are the younger leaves, about 8cm /3in long. It is a pick and come again crop use a knife rather than pulling off the leaves. For multiple harvests from the same plant simply pick the outer leaves and leave the inner younger leaves. Be sure not to damage the central terminal bud at the centre of the young growth. You can also if you wish harvest the whole plant.
Let the outer leaves grow as big as you want. If you can't eat it as fast as it is producing, cut and discard leaves as they begin to wilt. If the patch gets out of hand, do major surgery on the leaves. The inner leaves will take their place quickly.
As the weather cools, the leaves are their tastiest, if they turn a little too bitter in mid-summer, make sure to come back to them later. Harvests until the first hard frost, many gardeners pick Perpetual Spinach as late as Christmas!

Culinary Use:
After picking the leaves simply wash and add to salads or wash and then quickly heat in a pan using only the water that clings to the leaves after washing. This will avoid overcooked soggy leaves.
Perpetual Spinach does not store well so should either be eaten within a few hours of picking or stored in the salad box of the fridge for a maximum of three days.

Nomenclature:
The word Swiss was used to distinguish chard from French spinach varieties by 19th century seed catalogue publishers. The chard is very popular among Mediterranean cooks. The first varieties have been traced back to Sicily. Perpetual Spinach is a member of the beet family. …it just doesn't have a bulb!