Instructions: planting potatoes – timing, distance & Co

Potatoes need preparation

The usual potatoes in the pot bed are grown from seed or seed potatoes, and they first need a little preparation before they are placed in the bed:

• Seed potatoes are usually bought in winter
• And then pre-germinated, for most varieties from early / mid-March
• In an ambient temperature of around 10 ° C
• They have to be stored for two to three weeks in order to get in the germination mood
• Changing temperatures and fresh air should encourage the germination
• If they lie a little longer at these temperatures and get light, they will germinate

So you can choose whether you want to put potatoes in the germination mood or pre-sprouted potatoes, the latter is probably more relaxed for first-time potato planters because you can already see something.

The pre-germinated potatoes are “ready” when they show a germ length of about 15 to 20 mm. The advantage of pre-germination (or at least stimulation) is said to be that, in addition to rapid youth development, the potatoes grow more tubers and the potato plants are less frequently attacked by bacteria or fungi.

If you are a little late with the seed potatoes, it should be possible to germinate potatoes for three or four days in an environment with temperatures of around 20 ° C. This is the right potato preparation for all home gardeners who do not have cool adjoining rooms. In this case, however, you have to take special care that the potatoes, which have been put into a germinating mood in a rapid process with a lot of heat, are not placed in a soil that is too cool.

Location and soil preparation

While the potatoes are in the mood for germination, the location is determined and the soil is prepared:

Potatoes love the sun and should get a few hours of it every day, after all the Germans’ favorite side dish comes from South America. Our original potato is probably a descendant of a Peruvian Andean variety (which is not precise, there are more than 3,000 of them).

In any case, the potato is used to a lot of light and has no special demands on the soil. Potatoes thrive best in loose, sandy soils with a little loam. The water supply should be balanced and the pH value should be between 5.5 and 7. Potatoes neither like compacted, waterlogged soils (promotes net scab), nor too dry soils (then there is a risk of flat and humped scab).

You can mix clay into sandbox soils as clay powder (make sure you buy untreated natural clay), the potatoes are also happy about some well-rotten compost and well-rotten manure in the soil and then bring a higher yield.

Fertilization is already in progress, potatoes use up most of the nitrogen in the period from emergence (growth, young plant development) to tuber formation, and you don’t want to taste any of the fertilizer later.

If you previously had green manure in the bed, that is usually sufficient; in less well-supplied beds, you can also apply organic fertilizer from the trade.

Plants and plant spacing

When the potatoes are “stimulated” (really means that) and the ground is prepared, the seed potatoes can be planted. Provided that the weather plays along, a soil temperature between 15 and 18 ° C should already be, and above it preferably temperatures of 18 to 20 ° C, with a maximum night temperature of 15 ° C for optimal tuber formation.

So you should calculate a little beforehand when all of this will be on average in your region (no idea? Ask an experienced gardener) and start the pretreatment of your seed potatoes accordingly. A little colder or warmer doesn’t matter, of course, but temperatures below 10 or above 30 ° C cause the potatoes to almost stop growing.

When the weather is ready, the seed potatoes are planted in the bed:

• First make a furrow, or several, with a row spacing of 60 cm
• A little rotted compost can be placed at the bottom of this furrow
• A potato is placed in these rows every 30 cm
• Then you should pile the earth over the potatoes until a small dam results
• When the first shoots can be seen, pile up a little more soil
• If the frost should come again, the potatoes usually survive it well
• In cool areas you can also put a foil tunnel over the potatoes
• This makes the ground a little warmer and of course also offers additional frost protection
• As soon as the shoots are approx. 20 cm high, you should pile up more soil
• Then, in the darkness of the dam, bulbs without green spots will form
• Solanine, a slightly toxic substance, collects in the green areas

Planting time

Each of the many different types of potatoes (see below types and varieties) has an optimal point in time when they want to go into the soil. The cultivated potatoes are divided into early potatoes with a ripening time between 90 and 120 days, medium-sized potatoes with ripening after 120 to 150 days and late potatoes with ripening after 150 to 180 days.

Depending on the date of cultivation, you can start harvesting:

• Early variety, sown in mid-March: harvest in June and July
• Medium early variety, sown at the beginning of April: harvest July to September
• Late variety, sown at the end of April: harvest in September
• With the early and mid-early varieties, you have some leeway to the rear
• With the medium and late varieties, you have some headroom

Caring for the potatoes

Before the seed potatoes are planted, the soil cannot always be enriched with nutrients to such an extent that the high nutrient requirements of the potatoes are continuously met. Then the potatoes benefit from fertilization later in the year, which is definitely advisable if the shoots show signs of deficiency.

Deficiency usually shows itself in a discoloration of the leaves, depending on how this turns out, the fertilizer must be selected (you should be able to advise dealers of organic fertilizers).

The already described piling up loosens the soil and ensures good nutrient absorption. So you should also pile up in between when the dam on the bed becomes flatter.

The potato plant also needs enough water, of course, if there is no rain for a long time, potatoes have to be watered.

Time interval and crop rotation

Even home-grown organic potatoes can be attacked by diseases and pests if they are repeatedly grown in the same soil in which certain microorganisms accumulate.

It is therefore recommended to stock a site with potatoes only every three to four years. Since potatoes leave a lot of soluble nitrogen in the soil, which is at risk of leaching, plants that utilize a lot of nitrogen should be grown afterwards, or a corresponding green manure should be planted. This should not consist of perennial grass clover, which promotes infestation with wireworm, scab, dry core (fungus Rhizoctonia solani) and snails.

If the plants used work intensively through the soil with their roots, this reduces the risk of wireworms getting out of hand.

Since the nutrients of the potato should be available immediately after planting, any intermediate planting that promotes the soil structure and leaves a lot of easily decomposable organic material is particularly suitable. Among the useful plants z. B. deep-rooted herbs such as wild garlic, French beans, kohlrabi, salads and edible lupins. If it’s all about soil maintenance until the next potatoes, consider growing annual grass clover, broad beans, grain peas, and other root crops.

harvest

The harvest naturally depends on the date of sowing and the variety, see timing above.

The period of time over which you can harvest also depends on the variety: New potatoes can be harvested continuously when they are ripe. To do this, you carefully dig up the dams on the side, remove a couple of ready-to-harvest (correspondingly large) potatoes and then cover the rest again.

The medium and late varieties are all pulled out of the ground together on one date. Around the scheduled harvest date, take a quick look to see whether the potatoes have developed accordingly (dig up one or two). Then you should wait a few warm and dry days to harvest the potatoes. If they are to be stored (in a dark room or in a ground rent, dry and protected from frost), they can lie a little longer until they are completely dry.

Why grow potatoes

Certainly a good idea in rural areas with no lack of space. But to occupy the precious garden areas in the usually not exactly park-like house garden with potatoes seems rather strange at first, there are really enough potatoes in the nearest supermarket.

The first reason to “waste” part of the garden on potatoes is taste. The potatoes for sale are grown for yield, not taste, you can plant other seed potatoes. In addition, only organic potatoes have a chance to taste really like potatoes, see reason 3.

The second reason is the variety that is not available in stores (see types and varieties below).

The third reason is your health. Because conventionally grown potatoes don’t just end up on your table as they come from the ground, but they are treated after the harvest so that they always look chic in the supermarket. With chlorpropham, imazalil and thiabendazole, and those germ inhibitors and pesticides are just as toxic as they sound (usually included when it says “post-harvest treated” on the potato package). Here is an article about it: www.artikelmagazin.de/gesundheit/ernaehrung/chlorpropham-keimhemmer-auf-kartoffeln-wie-giftig-sind-pommes-co.html. The article is from the year 2011, but a search query for “potatoes”, “chlorpropham”, “last month” is the first to return a page for agriculture in April 2015,

The fourth reason for growing your own potatoes emerges from what has just been reported: You can harvest everything the soil has to offer, while conventionally only a small proportion of the potatoes are sold. Everything that is crooked, small, spotty, etc. is sorted out, which increasingly seems to be indifferent to us – more and more people spontaneously get in a bad mood when they hear about such nonsense.

The fifth reason is that the potato field in your garden doesn’t necessarily have to look like a potato field. Potatoes belong to the nightshade family, which also produce such beautiful plants as the peasant orchids (slit flowers, schizanthus) and the calibrachoa (balcony plant of the year 2012). Potatoes themselves also look pretty chic, with well-formed, dark green leaves and very attractive flowers, see: www.proplanta.de/Fotos/Blueten-der-Kartoffelpflanze_Bild1152709086.html. Nobody forces you to plant potatoes properly in furrows, you can try all sorts of designs with your own potato plants in the garden.

Species and varieties

Within the family, the potato belongs to the genus nightshade, Solanum, and forms the potato clade in the subgenus Potatoe. In addition to such exciting plants as Solanum blanco-galdosii, Solanum rhomboideilanceolatum and Solanum violaceimarmoratum, the tomato and the pepino (melon pear) also belong.

One species of this genus comprising around 170 species, the potato Solanum tuberosum, is the favorite of breeders, it has so far produced a good 5000 varieties, and there is no end in sight.

The varieties cannot be dealt with here, that would be more of a book project, already for the ones available in this country. Just this much: You can buy around 150 different types of potatoes from a well-stocked organic potato dealer.

You can choose the potatoes according to their ripening time (early to late, fast to slow). And according to the intended use, table potatoes, processing potatoes, farm potatoes, fodder potatoes, seed potatoes. The processing potatoes are the varieties for further processing into French fries, chips and potato flakes, commercial potatoes are grown for the industrial use of starch.

You can choose table potatoes according to their cooking characteristics (firm, predominantly waxy, floury, other types of cooking), according to meat color (white, yellow, pink, violet), according to skin color (yellow, red, blue, violet), according to tuber shape (long, oval, spherical, kidney-shaped) and according to the nature of the shell (smooth-skinned, rough-skinned).