Spinach is a hardy, healthy, easy-to-grow vegetable. Its tender, tasty leaves are fast-growing and it is an ideal cool-weather crop for spring or autumn.
Varieties of spinach are categorized by their leaf type: Savoyed, semi-savoyed and plain leaf. Savoyed varieties have puckered, wrinkled leaves. The leaves of semi-savoyed types are somewhat smoother. The smooth, oval leaves of plain-leaf types are the easiest to wash after harvest as they do not trap soil the way savoyed and semi-savoyed leaves do.
Varieties with erect leaves are easiest to harvest. The leaves often stay cleaner and can be quickly washed as well.
For late spring crops and in warm climates, select varieties that are heat-resistant or slow to bolt (go to seed). For autumn crops, sow seeds every two to three weeks from late summer to autumn once daytime temperatures begin to cool.
To grow your spinach crop you will need:
Blood & bone
1. Dig 3-5cm of compost into the top 12-15cm of soil in early spring to ensure fertile, moist but well-drained soil. Make sure you rake to bed smooth.
2. Sow the spinach seeds outdoors in spring or autumn when the temperatures allow. Space the seeds 15cm apart and plant them 1cm deep.
3. Sow new spring spinach crops every two weeks in the shade of taller crops until the weather remains above 20 degree C.
4. Keep soil evenly moist but not wet. Fertilize by spreading blood and bone along the rows when the first leaves reach full size and water in thoroughly.
5. Harvest spinach by pinching off outer leaves individually once they reach 10cm. Or, cut the entire plants off just below the soil level.
Encourage extra crops from spinach plants by cutting the whole plant back to 2cm tall when harvesting. The leaves often grow back.
Bolting, or going to seed, is a common problem with spinach, especially during seasons in which daytime temperatures remain above 20 degree C. Plant late-spring crops in partial shade and keep the soil moist to prolong the harvest. Discontinue planting until autumn when the temperatures no longer climb above 20 degrees C.
To extend the growing season, plant six seeds at a time, followed by another six seeds three weeks later. This will ensure a continuous supply.
A couple of suggestions when purchasing your spinach seeds:
Buy packets of several different types to see which ones grow best in your climate and which leaf type you prefer.
Avoid buying spinach plants in punnets, as transplanting causes it to bolt more quickly.
The sun and soil conditions that spinach loves:
Full sun to partial shade. Plant early spring spinach in full sun. Plant in partial shade later in the season for autumn crops.
Grow spinach in raised beds if the soil is not well-drained. A spinach crop prefers rich, well-drained, cool and evenly moist soil.
Interplant spinach with strawberries. The saponin within the spinach leaves is beneficial to strawberries.
Seasonal tips to remember:
In early spring sow spinach seeds as soon as the soil begins to warm. Sow every two to three weeks until the temperatures remain above 20 degrees C.
When harvesting in spring, pick the leaves once they reach full size or harvest the entire plants by cutting them off just below the soil level.
To prolong the harvest in early summer, water regularly and mulch to hold moisture in the soil.
Begin sowing autumn and winter crops when the temperatures remain below 20 degrees C and harvest when the spinach plants reach full size.