Where to Position Container Plants
Question of Location
Before choosing the plants for your balcony or terrace, you must first establish of the kind of micro-climate on your balcony or terrace. Does your terrace get full sun all clay long? Or does it overlook a shady courtyard? Or is it a roof garden exposed to all weathers, thus including strong wind?
You must also take the regional weather conditions of your area into account. These include for instance the numbers of hours of sun, the amount of rainfall, humidity of the air as well as, perhaps most important, the length and severity of the winters. Naturally, it is best to select plants whose natural growing conditions such as light, temperature, humidity andcorrespond to the conditions on your balcony or terrace. For instance, in a cool to temperate climate it is best choose native plants or plants that are native to regions with similar climatic conditions. As well as plants which in warmer regions are used to big differences between clay- and night-time temperature.
By careful breeding, horticultural growers have created many varieties that are much more tolerant regarding their growing conditions than in their wild form.
Most summer-flowering plants grow best in the sun. The ideal location is a south-facing balcony or terrace where they get the sun all clay long. Marigolds, asters, lemon and orange trees and michaelmas daisies as well as most herbs are among those plants that prefer a south-facing balcony or terrace. In fact, marigolds and Livingstone daisies only open in full sun. Some plants with silvery-blue or grey-green leaves, such olive trees, eucalyptus, cistus and lunaria are ideally suited for south-facing balconies and terraces. Because of their composition, these leaves heat up less and evaporate less water. Also leathery leaves such as laurel leaves transpire very little, as do the small, needle-like leaves of myrtle and rosemary. But the plants that are best equipped to survive long periods of drought aresuch as agaves and whose fleshy leaves are able to store water when it is available.
Sun with midday protection
Some sun-loving plants, especially those with large, tender leaves, need protection from the strong midday sun in summer. Plants such as angel’s trumpets and mallows will lose too much water through transpiration if subjected to the heat of the direct sun, and will wilt. They therefore need a position that is shaded from the heat of the midday sun. This protection could be in the shape of an awning, a sunshade or the moving shade provided by a wall or tree.
Sun to partial shade
Plants that grow in full sun and partial shade usually cause few problems. South-east or south-west facing balconies or terraces are usually ideal for these types of plants, which include Ageratum, trailing geranium,, Grass-of-Parnassus, violets and grasses such as sedge, quaking grass, fescue and moor grass. Plants with variegated leaves also prefer this type of location. They contain less chlorophyll than green-leaved plants and therefore need more light.
It is fortunate that there are also many plants which do not like too much light. They are ideally suited for partially shady areas because all they need are a few hours of sun in the morning or in the evening on the east or west side of the building. If they stand in full sun, the roots are not able to transport water fast enough to the upper parts of the plant. This shortage of water results in scorching of the leaves and the plants could dry up completely. Plants that grow best in partial shade include burning bushes,, , hydrangeas, busy lizzies and clematis.
The plants most suited for growing on cool, shady, north-west or north-east facing balconies or terraces include ivy, Japanese hop, spotted laurel,, periwinkles, coleus and most , which in nature grow mostly under trees where they get little light.
A shady location is particularly important for these plants during summer when the large soft leaves would heat up too much in the sun and become scorched as a result. They would also lose too much water. On the other hand, variegated species and varieties revert to green again in the shade.
Temperature depends not only on location but also on regional climate. Plants that thrive in warmth are happiest in regions where the number of hours of sun is very high and the winters are very mild-winegrowing regions in fact.
Plants of tropical origin such as bougainvillea, cassia and myrtle only grow and flower in relatively high temperatures, while plants native to coastal regions will grow happily in a cooler climate. Dwarf palms, fuchsias and laurel are more robust.
Wind and storms
In coastal regions there is always a stiff breeze on exposed terraces, high balconies and roof terraces. In this case you must choose robust plants such as juniper, broom or gingko that do not require warm conditions. In places exposed to the wind, plants dry out much more quickly. For instance, bamboos transpire so much water that it is very difficult to keep up with the watering. Plants with fragile stems or large, soft leaves such as cottonweed, aralias and willow would not be happy in such exposed locations.
In any windy locations it is also advisable to choose large containers for the plants so that they can store enough water in the soil. Large container-grown plants should be arranged in such a way that they cannot be blown over. Walls and hedges will protect the plants from the wind and provide a warmer microclimate in their vicinity. Roofed-over areas are ideal for plants that are particularly sensitive to rain such as smoke trees, oleanders, leadwort and many types of palms., which are native to regions where it rains very little, prefer excessively dry conditions to wet ones. and fuchsias on the other hand come from regions of the world with fairly high humidity and are therefore very happy during humid, cool summers.
Usually a tenant is allowed to decorate a balcony or terrace according to own taste as long as it does not disturb his neighbours. If window boxes are hung on the outside of a balcony or building it is essential to secure them properly. Also, make sure that when watering the plants the water does not run down the facade, onto other people’s gardens or property, or onto the pavement. The latter can be particularly dangerous in winter when it freezes. Before undertaking any building work on your balcony or terrace, such as a mini-greenhouse for instance, it may be necessary first come to some arrangement with your landlord or co-proprietors.
Pot Plants: The Right Container
When choosing a container, it is important to be guided not only by personal taste but also to make sure that it fits in with the environment and that it is large enough for the plant. Remember too that plants with shallow roots are more suitable for growing in containers than plants with deep roots.
Remember to take weight into consideration when selecting plants and containers for your balcony or terrace. A balcony should not be overloaded with plants and garden furniture, an approximate standard being 250 kg/m2 (50 lb per sq ft). However, this is also depends on the size of the balcony and the type of building.
There is a wide choice of shapes and materials available on the market and the guidelines below will help you make the right choice.
Balcony window boxes: These are usually plastic and come in colours ranging from brown, green, white to terracotta and standard lengths of 40, 60, 80 and 100 cm (16, 24, 32 and 40 in). Forplants, small and dwarf woody plants, we recommend large window boxes at least 20 cm (8 in) wide and deep so that the plants have enough space for the roots to grow. For larger herbaceous perennials and woody plants larger containers will be needed. Boxes with water-tanks are very practical because they will save a lot time in summer when the plants need a lot of water.
Hanging flower pots: These are available in various sizes and are usually made of plastic, their diameter ranging between 20 and 50 cm (8 and 20 in). Do not choose too small a pot because plants can grow very quickly when well looked after. It is important that they hang securely because they can become quite heavy after watering. Preferably they should be sheltered from the wind. There are also hanging flower pots with water-tanks. This will spare you the problem of watering ‘over your head’.
Pots and trays: the good old flower-pot still has its place on balconies and terraces today. Besides the tried and tested clay flower pots, there are now also plastic pots and trays that come in a variety of designs and colours. Imitation terracotta pots are very popular, one of their advantages being that they are very light and do not evaporate water so quickly. Pots are ideally suited for temporary or alternating arrangements because you can just place the pot where you want at the time.
Box or container: These come in a variety of materials such as plastic, stoneware, clay, terracotta or wood. In the case of larger containers, it is not only appearance which should be taken into account but also weight, especially if they are to placed on balconies and roof terraces. And do not forget that you must be able to move them even when they are full.
Milk churns and the like: You can also use your imagination and be creative. In every household there will be objects such as old milk churns, cast-iron cooking pots, a wheelbarrow or wicker baskets that can easily be converted into containers for plants. So as not to damage the inside of the container, it should first be lined with foil and make holes for drainage. If you cannot make any drainage holes in the bottom of the container, use clay shards or expanded clay to provide a layer of drainage. Wicker baskets should only be used for short-term planting.
Clay and terracotta: clay and terracotta containers immediately conjure up images of Mediterranean gardens. Terracotta refers to all unglazed clay pots. They allow good ventilation of the soil but this also means that it will dry out relatively quickly. This material meet the requirements of natural water-balance but is not so good for plants that need a lot of water. Quality varies enormously especially as far as frost-resistance is concerned. The harder the clay has been fired, the less water it will absorb and therefore the more frost-resistant it will be. In machine-made containers, there is often a deposit of chalk along the edge because the lime contained in the clay has not been completely burnt out. On the other hand, the development of a patina is a sign of good quality. The high price of hand-made clay pots as opposed to machine-made ones is therefore usually quite justified. Clay pots are heavy but at the same time their weight makes very stable. Unfortunately they are quite fragile.
Plastic: the advantage is that they are light in weight and comparatively cheap. The water evaporates very slowly, which is why plastic pots are recommended for moisture-loving plants. The soil warms up quickly but the plastic offers little insulation against frost. Their durability depends mostly on the quality.
Wood: a timeless material with a long tradition – think of ‘Versailles containers’. Wooden containers can be very robust and durable, depending on the type of wood. Oak, for instance, is very long-lasting. They are lighter than terracotta and provide good insulation. However, they are not weatherproof so they should be varnished or painted, and lined inside with foil.
Stoneware: Fired stoneware containers come in various qualities. They are often made in Asia. These glazed containers are both decorative and practical because they extremely weatherproof and easy to wipe clean. They do not develop chalky deposits on the sides. They are frost-resistant but are very heavy and not cheap. There are also containers made from ‘artificial stone’ that are cheaper.
Natural stone: Marble, sand or limestone can be used to make, bowls, vases, urns and much else. But they are heavy and relatively expensive.
Concrete: This is wind-proof and heat-resistant but very cold in winter and very heavy so it is not ideal for balconies. Concrete containers should be washed out thoroughly before planting and left outdoors for a long time before planting.
Fibrous concrete containers: These containers come in a great variety of colours and shapes and even include terracotta reproductions. They are made from cn mixture consisting of glass fibre, cement and other substances. They have several advantages since they are relatively light, resistant to frost and they ‘breathe’.
Important points you should remember:
• All containers must have an outlet hole at the bottom so that the plants do not become waterlogged.
• Never place the container directly on the soil but arrange it so that the water can drain away. Wooden containers will rot otherwise. Raise the container on wooden battens, bricks, terracotta or ceramic supports.
• Cylindrical shaped containers are best because they combine stability and manageability.
• Before using an unglazed clay container, soak it in a large container of water until no more bubbles rise from it, or leave in the rain for a few days.
• Medium-sized plants such as container plants , small trees or shrubs such as Christmas trees need a container at least 50 x 50 x 50 cm (20 x 20 x 20 in).