Spinach is a plant of its own in the foxtail family. The foxtails are a large family totaling around 2,500 species. However, only very few of these species are used by humans as vegetables (sugar beet, beetroot, chard, spinach, amaranth, quinoa), fodder plants (fodder beet), ornamental plants (garden foxtail, Iresine, silver smut) or medicinal plants (gland goose feet).
Table of Contents
background knowledge
The genus Spinacia itself does not produce much apart from the spinach. It actually only includes the two species “Spinacia tetrandra”, which grows in the Caucasus and western Asia on fields, in semi-deserts and on the shores of salt lakes. As well as the “Spinacia turkestanica”, which also grows in fields and semi-deserts. It is distributed from Central Asia to southern Russia, Tibet and India.
Because our vegetable spinach, the real spinach or Spinacia oleracea, is not known as a wild form. It probably originated in southwest Asia from the two wild species. A forerunner of this cultural form was probably cultivated in Persia and introduced by the Arabs in Spain, where it can be proven that it was first reported in the 9th century. The origin of the name also came from Spain, the Arabic name became “espinaca”. Here in Central Europe, the German scholar Albertus Magnus first described spinach plants in the 13th century. By the middle of the 16th century, spinach had already managed to displace the garden orache, which was popular in the Middle Ages, in many places.
The vegetable spinach was also able to assert itself very well elsewhere. Today it is the best-known representative of its genus and is so widespread in Asia, North America and Europe that it is sometimes even released into the wild.
Little known: There are many varieties of spinach
When a vegetable is so widespread, many breeders try to improve it even further. There are now about 50 cultivars of spinach. Lighter and more delicate varieties, dark and very spicy varieties, original and cold-loving varieties. As well as varieties where the breeders have intervened more so that they also tolerate higher temperatures. Here are some important varieties with the defining characteristics and possible growing times:
- ‘Emilia F1’ forms strong and thick-fleshed dark green leaves with a full flavor of spinach
- harvest from spring to autumn
- not prone to shooting in summer
- “Gamma”, a variety with dark leaves and late flowering
- Cultivation in spring or autumn
- “Lazio F1”, a fairly recent breed
- does not tend to shoot even when cultivated in summer
- Resistant to (downy) mildew
- “Matador”, old variety for cultivation in spring or autumn
- also suitable for overwintering
- late flowering and large round leaves
- robust, fast-growing and of good taste
- “Merlin F1”, a flavorful variety
- also suitable for summer cultivation
- not fully resistant to powdery mildew
- “Monnopa”, a mid-early variety
- plant in spring and autumn
- develops round, very dark green leaves
- Resistant to powdery mildew and hardy
- “Napoli F1”
- plant in spring and autumn and overwinter
- growing fast
- is considered to be very productive and very tender
- mildew resistant
soil and location
You should look for a sunny to partially shaded spot in the garden for your spinach, with nutrient-rich hummus soil with a pH value between 6.5 and 7.5, which should be prepared with a generous dose of compost before sowing. You should loosen the soil a little right away, the deep-rooted spinach should get the chance to penetrate deeper soil layers.
How much space you plan for depends on whether you want to plant the spinach alone or combine it with other vegetables as a pre-culture or post-culture. This community culture is the actual, traditional way of growing spinach. The experienced vegetable farmer actually only plants the spinach in post- or pre-culture because it is simply ideal for this. First, most spinach varieties do best when the season features short days and long nights. When normal spinach plants experience endless summer days, they tend to shoot through. In addition, the spinach, with its long roots pointing steeply into the ground, wonderfully loosens the soil far into the ground. Other types of vegetables also like to grow in such soil.
Depending on the region, spinach as a preliminary crop can be sown from the end of February when the soil is already open. That should be the end of it around April. Normal spinach varieties would then have to be harvested fairly quickly before the spinach starts to shoot. You can sow the planned next vegetable between the spinach plants before the spinach is completely harvested. You can sow or plant almost anything that comes into the ground from July onwards with the spinach. Autumn spinach is sown between August and September, e.g. B. as a follow-up crop for new potatoes or peas or on a strawberry bed that has already been “mowed”.
neighbors for spinach
Spinach goes particularly well with potatoes, cabbage, kohlrabi, radishes, radishes and tomatoes. In fact, spinach can be grown in a mixed culture with almost any vegetable. Even with other heavy eaters if you just want to toss it in the cooking pot. A little loss of aroma can be quickly compensated for with spices.
Unless the neighbors were allelopathically active plants and the interactions that occurred were negative. Allelopathically active plants release chemical substances (allelochemicals) that cause something in the neighboring organism, sometimes something positive, very often something negative. And the spinach behaves like a real “top dog” in this respect. It has a negative effect on plants that, like it, belong to the foxtail family. It is known that Swiss chard, beetroot, sugar beets and fodder beets do not thrive next to spinach. At the same time, this means that the spinach is not a suitable successor for a location where other foxtail plants (or itself) grew. This bed should be given a break of 2 to 3 years between the cultivation of further foxtail plants.
If you want to plant spinach alone, there are now some varieties suitable for summer sowing that do not immediately start to “shoot” even on long summer days. “Emilia F1”, “Lazio F1” and “Merlin F1” for example.
Depending on whether your spinach will be left alone or cultivated in company, you will of course have to measure the distance between the rows. “Spinach only rows” are placed about 20 cm apart. The spinach plants themselves also need a bit of space to the right and left of each other. A few centimeters are enough here.
When all of this has been considered and executed, the soil should be well moistened before you start sowing.
The sowing of the spinach
Spinach is sown directly outdoors. With spinach, don’t worry about using last year’s leftover seeds, they will germinate for quite a long time, three to four years.
The seeds are now placed in the prepared soil in the imagined “row design”. In the case of dark germinating spinach, the seed must be covered by soil, it can be one to three centimeters. Then step or tap the row of seeds once. This gives the seed the close soil contact it needs to germinate.
If you sow spinach very early or very late in the year, it is best to cover it with foil until it is warmer again. Otherwise you will train your plants to shoot, because young plants or plants that are just starting to sprout like to think they “have to catch up on growth” if they have had to endure cold temperatures.
pour
The spinach is already sown in a well-moistened soil. The soil should stay like this throughout: always a little moist, but please without waterlogging. If it’s very dry outside, be careful and water sufficiently. If the spinach gets too dry, it wants to save the survival of the next generation and starts flowering as quickly as possible. This makes it unusable.
Fertilize
If you have prepared the soil well with compost, the spinach no longer needs very much fertilizer. You can only add a little more compost when the young plants are already quite strong but there is still at least a month left before harvest.
Under no circumstances should you “overwhelm” the spinach with artificial fertilizer, at least not if you are not a trained fertilizer specialist. With the uninformed application of this artificial fertilizer, you have the best chance of increasing the already critical nitrate and oxalic acid content of the spinach.
Nitrate can become nitrite, under all sorts of conditions such as heating several times, not cooling enough, etc., bacteria that bring about this conversion multiply. This nitrite is converted to nitrosamines under certain conditions during cooking or after consumption, and these are known to be carcinogenic. Sufficient vitamin C, which is also present in spinach, should prevent this, but you should certainly not actively promote the nitrate content in spinach with chemical doses.
Oxalic acid reacts with the calcium compounds in our body to form calcium oxalate, which is very difficult to dissolve, and thus disrupts the calcium metabolism. Too many calcium oxalate crystals are said to turn into kidney or bladder stones.
It would probably be wisest if you put the spinach in a well-prepared, humus-rich soil that has not been contaminated with artificial fertilizers or other previous over-fertilization and then stop fertilizing at all. Because the spinach you buy has mostly been artificially fertilized. It must not exceed certain maximum values. To appreciate these maximums, you would first need to study chemistry and also know if industry associations had a hand in setting these maximums. So you really only have the chance to grow a highly uncontaminated spinach with the spinach from your own garden.
Spinach plants overwinter
If you want to harvest spinach in early spring, there are various varieties (see above) that you can sow in September and overwinter. However, if there is a risk of dead frost (frost without snow cover), you should cover the young plants.
Harvest spinach
You only have to wait about eight weeks after sowing before the first spinach can be harvested. You then do this by cutting off individual leaves around the heart just above the ground. You are welcome to harvest regularly. New leaves are constantly developing from the heart inside. Constant pruning promotes further growth.
Spinach should always be harvested in the evening. Under daylight, photochemical processes take place in the plant, during which the nitrate contained is converted into plant-specific substances. As soon as the spinach flowers, you should stop harvesting altogether, because the spinach has the highest concentration of nitrates during flowering.
multiply
All spinach cultivars are annual vegetables. However, if you have seeded spinach varieties that overwinter in your garden, you can let a few plants of this spinach flower in the spring and use these plants to seed the next spinach later.
Conclusion
Growing spinach in the garden is easy to care for. If you grow, prepare and store it properly and don’t use it every day, you’re also likely to benefit from the healthy ingredients like vitamins A and C and beta-carotene rather than the critical ones (although the legend of the high iron content may be misplaced set comma was created). Only babies should not be given spinach under any circumstances, they lack an enzyme that protects them from severe damage from spinach or other nitrate-rich vegetables.
