Urban gardening is far more than a trend, it is an expression of a philosophy of life. More and more people are realising their desire to grow their own vegetables, herbs and fruit in organic quality, even though they have a balcony instead of their own garden. “Organic gardening succeeds even on a few square metres if a few rules are followed,” says Herbert Vinken. He has been focusing on ecology for many years in his organic market garden “herb’s” in Dötlingen, Lower Saxony. “Vitamin-rich vegetables like tomatoes, lettuces, peppers, radishes, kohlrabi and aromatic herbs can be grown in pots, it’s not witchcraft. Properly planned, it’s harvest time from spring to autumn.” And if there are a few more pots to spare, the organic gardener recommends using them for rarely planted delights such as country cucumbers, peas, parsley roots, beetroot, carrots, onions, potatoes or various spices.
Step 1: The right choice of location and soil for pot planting on the balcony
The successful cultivation of wholesome vegetables and herbs succeeds with a few basic skills, as numerous reference books suggest. The choice of plants naturally depends on the preferences of the balcony gardener. However, the location of the balcony sets limits: The better a location suits the plant, the easier it will grow. Since not all plants can tolerate sun, shade or wind all day, it is worth finding out about this before buying.
Gardening on north-facing balconies can become a real challenge. “Plants need more space there and a few hours of sun per day are vital,” says Herbert Vinken. “Equally important, but easier to influence, is the quality of the soil, which should be as peat-free as possible, especially in private gardens.” For the organic gardener, a good soil consists of high-quality humus and mineral components. It stores water and nutrients, while at the same time ensuring good water drainage. High-quality soil does not collapse after a few weeks and continues to absorb water even if watering is not done regularly.
“If you don’t have well-rotted garden compost, you have no choice but to buy bagged compost. When doing so, look for peat-reduced mixtures, compost with a RAL quality mark and organic fertiliser,” advises the expert. He warns: “Please do not save in the wrong place, because good soil is not called ‘topsoil’ for no reason. Often, however, the soil does not deserve the name, especially if it is an inferior, bargain-priced product with cheap Baltic peat and colourful fertiliser balls that have also been transported a long way. Regional plant soil is often the best solution.”
Step 2: What do the roots need?
“Again and again I am asked why parsley, for example, does not grow as luxuriantly in pots as it does in the garden,” Herbert Vinken reports. “The answer is very simple: plants can only grow as well as their roots can find space in the planter. That’s why umbellifers like parsley, fennel or carrots need deep, loose soil – or even a deep container that doesn’t even have to be particularly wide.” However, Vinken points out that carrots tend to struggle in any pot. However, many vegetables thrive on the balcony, provided they get at least half a day of sun.
However, plants that are less deep-rooted but rather wide-rooted can also be best placed in boxes. “Picking lettuces are shallow-rooted and really only need good soil and regular watering. If you want to sow them yourself, you should put a few centimetres of nutrient-poor sowing soil on top of the plant soil.” Expert Vinken likes to mix a few old varieties in with the familiar ones. “If space is limited, lettuces such as Asian collard greens, also called mizuna, are suitable. They are easy to grow yourself or to buy from an organic nursery or mail-order company.”
While Asian lettuces germinate outdoors in cooler temperatures, warmth-loving species such as chard, lettuce or kohlrabi have to be grown indoors early in the year – around the beginning of March. “Once they have reached a certain size, they will use their roots to get the nutrients from the plant soil further down on their own,” says the expert advice.
Step 3: Which pot should I choose?
Which pots to use for the balcony depends on the circumstances, the space and the budget. If balcony pots are fixed, make sure they have drainage that works all year round. Those opting for pots have a choice between plastic, clay or zinc sheeting. “This is not a question of faith,” the garden expert clarifies. Often the floor plays a role in the choice. Many balcony gardeners shy away from placing heavy clay pots on the upper floors of their balconies for fear that they might fall down.
There are advantages and disadvantages: “Plastic pots are light, hold water better than clay pots, but need a lighter soil so that enough air gets to the roots. This can be achieved with about 10 per cent hydroponics expanded clay,” the practitioner explains. “Terracotta is fancier, but much more expensive. And even more expensive if it is to be guaranteed frost-proof. Still, many opt for the airy clay, which allows Mediterranean herbs in particular to thrive.” Those who choose the inexpensive, decorative zinc containers should make sure that they are not placed in the blazing sun. Otherwise it gets very hot in the zinc boxes that the roots and the soil life heat up strongly. As a result, the roots die quickly and harmful fungi can develop. Zinc materials should only be used as planters in the sun, it is recommended.
Step 4: Distance please! Pricking out
Many plants can be grown early in the year on the windowsill. Before buying organic seeds, it is advisable to make a small plan, which can easily be done with the help of a sowing calendar. With the right timing, you can plant several crops that grow in succession, such as radishes, then lettuce and finally lamb’s lettuce. As soon as the seedlings have reached the right size, they are pricked out. The seedlings are carefully picked out of the seed tray and transplanted into individual pots. It is important to leave enough space between the seeds to allow room for growth.
If you find it too tedious to grow your own plants, you can use seedlings: “As a rule, these are plants that are more robust and a few weeks older than the plants from the nursery, so that they survive transport undamaged. Gardening is always worthwhile and even in the smallest of spaces, Herbert Vinken is convinced. Sustainably and ecologically grown, the harvest is a healthy treat.