I have a dear old friend, Thomas, who raises organic vegetables in timber barrels. Several decades ago, well-used barrels were frequently discarded from the larger vineyards and distilleries or sold to gardening enthusiasts for a modest sum. Nowadays, the use of wooden barrels is greatly diminished as inexpensive alcoholic beverages are increasingly stored in stainless steel kegs. Consequently, the few wooden barrels currently available have become sought after items. They’re typically sold by outdoor design centers and antique dealers for upmarket prices. My friend recalls two men offering several thousand dollars for his collection of barrels. It was Easter Sunday and they were offering cash, he explains. They had their truck with them and they seemed pretty confident about purchasing his barrels. What’ll you do with them? inquired Thomas. Saw them in half, varnish them, and mount them on decorative stands. Sell them on the internet. On the internet? Thomas repeated. Yeah, they confirmed, decorative containers are popular on ebay.

The main challenge for the gardener interested in container grown vegetables is to select suitable varieties and to accommodate their individual requirements for space, water, sunlight, and nutrients. Container raised vegetables are susceptible to crowding, more so than those planted in open ground. Deep and spacious containers like those wooden barrels are ideal for growing small quantities of organic vegetables, particularly the green leafy varieties and compact growers like cherry tomatoes, and snow peas. Leafy vegetables like spinach or silverbeet grow surprisingly quick and even regenerate themselves after picking. Potatoes can be grown in troughs or drums which are simply emptied at harvest. There are miniature varieties of carrot and other root vegetables which have been refined for container growing. Containers are inappropriate for several classes of vegetable. Heavy feeding plants like corn are better served in open ground and the larger spreading vines like pumpkin, marrow, and aubergine will struggle to reach their potential when planted in containers.

When grown in open ground, vegetables can extend their roots over distances to obtain sufficient water in dry conditions. Because of their restricted root systems, container-grown plants require more frequent watering. At the peak of a dry summer, this may increase to several times each day. Automatic sprinkling systems can be programmed to deliver measured volumes of water at intervals throughout the day and evening. These units are extremely valuable in gardens supporting a large number of containers. The down side associated with frequent watering is the potential for drainage problems combined with a continual washing away of water-soluble nutrients. Providing regular replacement in the form of a liquid plant food can usually offset the loss of nutrients. The best organic products include seaweed extracts, liquid manures, and milder solutions brewed from nettle or comfrey leaves. While expensive, commercial organic supplements improve the overall quality and yield of container-raised produce. These should be carefully diluted according to each manufacturers recommendation. Excessive concentrations cannot be absorbed and will eventually damage root structure and function.

In the absence of good drainage, planting containers may eventually become waterlogged, damaging vegetables by restricting the uptake of oxygen from their roots. Drainage is determined by the availability of porous channels which absorb then direct water towards the base. Upon reaching the base, excess water is encouraged to drain externally from the container. Good drainage can be assisted by using quality organic potting mixtures, above a base layer of scoria or ceramic and by ensuring that pots and tubs have several drainage holes that are at least two centimeters in diameter. Most garden soils tend to compact with frequent watering so are not recommended for container planting. The best potting mixes contain fibrous organic materials that hold an even dispersion of moisture and air pockets plus nutrients to support plant growth. The mixture must also be sufficiently dense to support the vertical growth and weight of plants. For growing vegetables, my friend Thomas uses an organic potting mix combined with sandy loam in approximately equal quantities. He completely replaces this growing medium after each crop of root vegetables. For his tomatoes and leafy greens, he generally replaces this after harvesting a second or third crop.

The metabolic rate of all green plants is determined by the availability of light and heat. There is quite a bit of variation in the optimum sunlight requirement for the different types of vegetable which are commonly raised. Spinach, for example grows happily in restricted sun or partial shade whereas most tomatoes require direct sunlight for at least four or five hours on average per day. Most container-grown vegetables require good ventilation and at least several hours of sunshine each day. Their location must be carefully chosen to avoid difficult and extreme weather conditions. Enclosed patios are usually suitable but open and elevated apartment balconies are often subject to extremes of heat, cold, wind, and rain. While the Mediterranean or European tradition for growing vegetables and herbs on raised balconies is a cultural tradition, there is a potential safety hazard when heavy planting vessels are positioned on elevated surfaces. Call me anxious, but I cannot avoid checking upwards on visits to Spain and southern Italy. My friends laugh because I still grab every opportunity to browse around the fashionable terraces of Messina and Palermo.

Now those ebay entrepreneurs were pretty keen to purchase old Thomas’s barrel collection. They added an extra hundred to the original offer. Thomas admits being tempted. The barrels were pretty old, he says. He thought about raising vegetables in deep acrylic pots. In the end, I couldn’t, he reveals. You’d become attached to the natural timber? I ask. Yeah, I suppose so. Those barrels are the functional elements of my garden and they were planning to cut them longitudinally. Shallow trays for temporary flower displays? He scratches his head with disbelief. Their shape is kind of important to me, he asserts. I admire rounded things with pleasant curves. Like those old Buick passenger vehicles of the nineteen fifties. You don’t interfere with a brilliant design.   

Growing in containers provides a great deal of flexibility and solves problems that might otherwise limit the creativity and enjoyment of organic gardening. Containers provide the essential platform in garden locations without soil such as patios, paved courtyards, and roof areas. They may offer the only means of gardening for individuals living in flats or apartments with limited space. Many urban dwellers have enriched their lives by growing collections of herbs in pots and containers on a windowsill. Most importantly, containers can sustain a range of plants that will struggle or fail in local soil and conditions. For example, in climates where the winter would normally kill a lime or tangelo, these can be grown successfully in containers, so long as they are carefully located in a sunny position and protected against extremes of cold and frost.

A collection of containers is capable of exhibiting a diverse range of plants and enables them to be creatively arranged according to mood or situation. Plants can be relocated to take advantage of contrasting colour, height, and shape. Those with the healthiest foliage or that have commenced flowering can be moved to a more prominent location. The possibilities are almost infinite.

Pots and containers

Pots and containers come in a wide range of size, style, and quality. Traditional stone and terracotta pots grow more beautiful with the patina of weathering and their earthy tones provide the perfect complement to subtle shades of flower and foliage. They are not as common or popular with gardeners today but can still be purchased from artisan manufacturers in most larger cities. One of the slight drawbacks with terracotta is its porous permeability. Plants growing in terracotta vessels will generally require more frequent watering than those in glazed ceramic, plastic or metal containers.

Good quality glazed ceramic containers tend to be heavy, expensive, and not as widely available as they were several decades ago. They can occasionally be grabbed for bargain prices at garage sales and opportunity shops. For serious gardeners, it is well worth investing the money or time to secure these. Properly cared for, they will last and with their beautiful shapes and brilliant glazes will add to the overall vitality of a container garden.

Plastic containers are cheap, light, easy to obtain and come in a spectrum of shapes, colors and styles. Despite their many advantages they lack the character and substance of ceramics. For some individuals, a garden dominated by disposable plastic containers might even conflict with the underlying philosophy of an organic approach. Metallic containers include those made from copper, brass, aluminium and stainless steel. They are often painted however the raw metal can look attractive in some settings particularly where the surfaces have been allowed to weather and mature naturally.

Recycled objects

Another option for the container gardener is to make use of recycled objects. This invites a creative approach, since a seemingly random collection will eventually suggest its own unique sense of individuality, humour or theatre. Old boots, buckets, a watering can, a hollow tree stump, toilet bowls, a spare tyre, even a bathtub are all possibilities to be entertained and there are certainly always more be discovered.

Whatever the choice of container for planting, there are several important characteristics which should be standard. The size of a container will determine the type of plants that can be grown. Shallow rooted varieties like lettuce or chives will manage adequately in smaller pots with a depth of around twenty centimetres. Most varieties with longer roots will require larger and deeper vessels. All plant containers require holes in their base to facilitate drainage. It is standard practice to place a shallow layer of gravel over the base of containers before filling them with potting mix. This ensures an adequate drainage that prevents the mix becoming waterlogged and subsequently drowning the roots.

Watering

Determining the appropriate frequency and volume of watering is one of the most important and challenging aspects of container gardening. In warm, dry conditions, potted plants generally require an automatic watering system or fairly constant attention. In cooler weather, the main risk is over watering and eventually drowning the roots. Sometimes the surface of the potting mix will look and feel dry but it is important to dig a few centimetres below this base. When a sample of mixture taken from this depth feels slightly moist and springs back when pinched between the fingers, there is no need for additional watering. Obviously, the ideal situation is to maintain this level by replacing water at the same rate it is drained, evaporated and taken up by the roots. This is where an automatic watering system or patience is required.

Potting mix

Plants housed in containers require an organic potting mixture since they will not usually obtain enough nutrients from ordinary garden soil. In addition to plant nutrients, organic mixtures provide water and air for the roots. Like sponges, good quality mixtures are structurally designed to hold a separated dispersion of air and water particles. When saturated by over watering, the mixture tends to break down, air particles get displaced, nutrients are washed away, and the overall structure is weakened. While most commercial varieties tend to be excellent and convenient products, it is certainly possible to make organic potting mix at home using combinations of natural materials such as loam, garden and worm composts, leaf mould and seaweed extracts. The exact recipe for each mix will vary with the type of plants and their particular climate and growing conditions.

Location

Most potted plants will benefit from a location that receives plenty of sunlight and a good circulation of fresh air. During the peak of summer, try to secure some shade relief for sensitive plants. Particularly in the tropics and sub-tropical regions try to be alert for any weather forecasts of severe rain, hail, or wind. In these situations, smaller containers can be carried indoors, while any that are too large or heavy need to be secured and protected as much as possible.

For absolute beginners or those without the space for a proper garden, containers can be stacked on a balcony or windowsill to provide a small but exciting range of fresh produce. The best plants to grow are smaller varieties with leaves or fruit that can be picked for salads. Herbs like thyme, basil, chives, and garlic are a great choice. Simple salad preferences might be lettuce, cherry tomatoes, peppers, and courgettes. For a slightly more exotic taste go for combinations like endive, mustard cress, chicory, sorrel, and coriander. Remember that most varieties of lavender are beautiful, strongly scented, and an ideal companion plant for edible herbs. Lavender is easy to grow and attracts beneficial insects while helping to repel pests like aphid and mite. Ornamental fruit trees do particularly well in medium to larger size containers. Citrus fruits require lots of warm sunlight but pears and apples will be fine in most cooler climates.

A collection of pots, plant boxes, small barrels, and other portable containers will provide a degree of control and versatility that is not often possible when herbs are planted directly to the garden. Most herbs are reasonably adaptable to a range of soil and climatic conditions. However, like any species there is usually a preferred range that will promote healthy, vigorous growth along with increased flavour, nutrient profiles, and therapeutic potencies. For example, basil flourishes in rich, moist soils with a slight acidity, whereas oregano, thyme, and sage all prefer soils which are lean, with a neutral or alkaline pH.

In each instance, organic growers must exploit the preferred range to reduce the risk of their plants developing the type of problems which are normally treated with chemical compounds. Many of the popular culinary herbs enjoy full sunlight and relatively warm soil temperatures while some cosmetic and therapeutic herbs like soapwort and pipsissewa require partial sunlight and cool soils. By making use of the different micro climates within each growing region, dedicated organic practitioners may introduce a wider range of herb species into their gardens. Many of these plants will be susceptible to extreme conditions and may need to be sheltered against sudden cold, heat, strong winds, frost and dryness. Whenever these exotics are housed in portable containers, the task of rearranging locations to accommodate prevailing garden conditions becomes much easier.

There are several species of herb which are notorious for their ability to spread widely, and, when provided with suitable growing conditions they can dominate an entire garden and risk choking or out competing rival plants. Examples of these are the common mint varieties, Vietnamese mint, and horseradish. Once herbs lose their cultivated status, they are likely to be considered common weeds, particularly where they invade surrounding properties. This can be particularly damaging when uncontrolled growth occurs within pockets of native or restored vegetation.

Due to the pressures of urban consolidation, many of these areas support ecosystems which are increasingly fragile and vulnerable. The introduction of exotic species can disrupt patterns of native vegetation and will in turn upset the balance of other organisms which compete for limited amounts of light, food, and space. For this reason alone, it can be tremendously advantageous to restrict the growth of certain herbs by keeping them secured in planting pots or containers of some description. This practice is particularly well supported by organic growers and others who depend upon the integrity of their surrounding environment.

Larger pots will support a decent crop of herbs and the supply can be maintained or increased as required. Maintenance requires a well drained potting mixture, and the occasional application of liquid fertiliser such as an organic seaweed or nettle extract.

The majority of herbs are perennials which will attempt to seed or reproduce by division prior to the conclusion of their growing season. The horizontally spreading herbs like Vietnamese mint can be divided and repotted during the spring or summer. Do this by splitting the crown of the plant into several pieces then replant using an organically certified potting mixture. Any additional runners attempting to escape over the sides can be trimmed then repotted. Regular harvesting will limit the plants ability to spread. To prevent unwanted regrowth, excess foliage and cuttings must be incinerated or finely shredded before composting in a biologically active heap.

Beautiful and creative cooking requires the combination of many technical skills and an imaginative inspiration. With dedication, the technical skills will eventually be mastered, but the imaginative qualities must arise effortlessly from the surrounding environment. Whether these emerge through the influence of personal relationships, fine art, music, literature, or nature itself, the experienced will appreciate the importance of making enough space for the imagination. For the suburban or inner city apartment with limited room, a well considered collection of potted herbs can help to create a compact and inspiring oasis, perfect for calming the mind at the beginning and end of each day.

Perhaps the only space available for growing herbs is the enclosed courtyard, or a small balcony or windowsill. In addition to cacti and miniature citrus trees, herbs represent an excellent choice for a balcony or windowsill planting. However, depending on their orientation, both these sites can be notoriously exposed to drying heat and wind. Most of the fragrant or culinary herbs from Mediterranean and North African climates will survive these conditions with few if any concerns. Try rosemary, thyme, marjoram, lavender, sage, parsley, garlic, and cardamon. Larger containers are preferred since they are less likely to topple over and will require less frequent watering to ensure a moist and well drained potting mixture. The best herbs for growing in full sunlight are sweet basil, chives, dill, and coriander. Individually and combined, these herbs will contribute to the enjoyment of many culinary dishes. Even the scented leaves of lavender may be added to salads, exotic jams, and jellies, or dried in tea to provide a fragrantly warming drink with a mild sedatory effect.

Ideally, the choice of individual herbs and their arrangement should reflect some aspect of the gardener’s interests and personality. An artistic arrangement based on subtle harmonies of texture and colour might well include small and medium size pots containing lemongrass, orris, tarragon, and aloe vera. On account of their aromatic and volatile constituents, freshly cut, dried, and living herbs can be used to influence the emotions.

From their reputation and documentation throughout history, several herbs are clearly associated with religious and spiritual practice. Establishing potted herbs like bergamot, chamomile, and sage near a doorway or sheltered balcony can help to promote a calm state of contemplative awareness. Herbs which possess energetic and invigorating properties include basil, coriander, ginger, mustard, and turmeric. Individuals with a passion for craft may enjoy experimenting with scented mixtures of dried herbs. When bunches of dried lavender are sewn within miniature pillows, they can be decorated and used to freshen any enclosed space. When taken to bed, lavender scented pillows help to promote relaxation and sleep.

A few organic growers continue to avoid raising herbs in pots, usually because they require additional mineral supplements and feeding several times each year. While there is less opportunity to incorporate large quantities of organic material, the basic principles of soil improvement still apply to container gardening. There is no reason why a garden of potted herbs should not be integrated into the wider environment.

Thoughtful recycling is an important component of the organic philosophy and its practical approach to gardening. Rather than wastefully discarding herb clippings and other organic scraps from the kitchen, these can be converted into a valuable organic supplement which is used to enrich soils and promote productivity. A worm farm can be started from scratch or purchased as a kit from an organic nursery, hardware store, or council depot. Worms require a moist and cool environment and small amounts of food offered frequently. Unless there is a problem, active worm farms are relatively odourless. If an unpleasant smell occurs, the worms have probably been overfed, causing their undigested food scraps to decay. This process is accelerated in warm conditions, so ensure there is sufficient shade to protect the worms and discourage unwanted decay. The complete kits contain detailed information about bedding and feeding worms along with instructions on gathering the vermicast and liquid compost.

Many fruit trees or vines can be successfully raised in containers. Within the average suburban allocation, container planting enables a wider diversity of species to be trialled, particularly when there is an appreciation of the various micro-climates and other growing conditions. In most regions it is important to make use of sunny, but reasonably sheltered spaces around walls, pathways, trees, and other decorative features. With the exception of very large specimens, container growing has the advantage of portability. Containers can be moved to accommodate seasonal shifts and to avoid the impact of storms and predatory insect attack. Water supply and drainage can be closely monitored and problems are often easily fixed, before any serious damage is suffered by plants.

Growing fruit in containers can be particularly suitable when a large section of garden is devoted to vegetables or flowers. Depending on the type of fruit chosen, watering and cultivation requirements may be incompatible with other plants. Despite their need for individualised attention, fruit trees and vines will benefit from basic organic techniques such as natural soil enrichment and companion planting.

Most reputable organic nurseries, offer an excellent variety of miniature fruit trees and vines which should be acclimatised and suitable for localised conditions. Smaller growing citrus trees like mandarins, cumquats, and meyer lemons grow well in large containers. When maintained in healthy condition, the trees should have glossy green leaves throughout the year and delightfully fragrant blossoms in Spring. Upright varieties of apple and pear grafted onto dwarf rootstock are also well suited to container growing, particularly in cooler climates.

Some other fruits to consider for a container garden are figs, avocado, olives, guava, and lychee. A good strategy involves choosing a selection which provides edible fruit several times throughout the year. An alternative is to focus on those seasonal fruits which can be readily preserved in jams, chutneys, and relish. Some gardeners prefer fruit trees that require little or no maintenance while others base their selection on favourite and preferred eating varieties. Several popular fruit species can be challenging to raise on account of their predisposition to disease or complicated pollination requirements. Examples include stone fruit like cherries, peaches, and some of the traditional varieties of grape and strawberry.

It is most important to choose the correct size, shape, and composition of container for fruit trees and vines. While attractive to look at, very small pots and containers can be difficult to manage, mainly on account of their tendency to absorb heat rapidly and dry out.  This drying will often create a surface crust which repels water and prevents normal drainage. In these situations the container must be removed from direct sun then placed in a bowl of water to enable the plant roots to absorb moisture from below. Containers made from plastic and other synthetic compounds are inexpensive to purchase but do not contribute much in the way of aesthetic beauty or elegance. In addition to this, the manufacture of plastic releases toxins which are damaging to the environment. On the positive side however, plastic is considerably lighter and less prone to breakage than other suitable materials.

The traditional material for garden containers is terracotta, beautiful in appearance due to variations in colour and texture which become exaggerated with weathering. Due to their permeability, terracotta containers generally require more frequent watering than plastic. Concrete is somewhat less permeable than terracotta however the larger sizes are terribly heavy and awkward to move about. Don’t even think about moving them when they are planted out with soil and potting mixtures.

Depending on the style of garden, various discarded objects can be recycled for good use. Once drainage holes are drilled into their base, empty wine barrels make suitable containers for small fruit trees. Old fashioned laundry tubs make excellent containers for spreading vines such as grapes, blackcurrant, and passionfruit. When correctly chosen, the original container will be sufficiently large to accommodate the mature specimen, without the need for replacement or replanting. 

When preparing a container, ensuring adequate drainage is the initial and most important priority. A layer of broken crock, bricks, or volcanic stones is followed by several inches of coarse gravel, raked level. Before proceeding it is a good idea to pour water over the gravel and ensure that it drains rapidly through the holes at the base of the container. The next layer is the humus rich potting mixture that will provide essential nutrients, as well as sufficient water and oxygen for the growing plants. The potting mixture can be prepared with natural organic ingredients or one of the commercially blended organic varieties which avoid the artificial fertilisers and other chemically treated ingredients. An even sprinkling of sandy soil can be used for the uppermost layer, allowing the container to remain unfilled by at least an inch. The new container should be watered and kept moist until planting. The ideal situation is for the mixture to support an even distribution of moisture. Elevating the containers on bricks or other suitable supports, will enable excess moisture to drain freely from the holes in the under surface. This practice prevents easy access to many crawling insect pests and also protects against invading roots from grasses and weeds.

Unlike container grown herbs and most flowering annuals, fruit trees and vines need to be provided with additional nutrients, particularly when the fruit is beginning to set. Immature trees need to become established before regular manuring due to the sensitivity of their roots. A few handfuls of old, well rotted compost or very weak liquid manure can be sparingly applied to young trees every few months. Once established, small amounts of organic compost should be mixed into the surface every other week. Worm compost is a very complete source of natural nutrients. Another option is to use finely shredded seaweed or dried horse manure sourced from organic certified pasture. These treatments should prevent the mineral deficiencies which frequently underlie fruit rotting and crop failures. To discourage disease, fallen fruit and leaves must be removed each week. Any fruit exhibiting symptoms of fruit fly or other infestation should be excluded from the compost heap and safely buried or incinerated.

To bear a decent crop of organic fruit each year, most container grown fruit trees require some periodic shaping of their branch and foliage structure. Organic tree nurseries tend to shape their juvenile trees into a chalice configuration with multiple branches spreading outwards to provide an open centre. An alternative is the pyramid shape with a well defined vertical trunk from which a fixed number of lateral branches radiate. The chalice configuration is particularly suitable in colder climates since it allows more sunlight to reach the central portion of the tree. In very dry and heat prone areas, the pyramid shape provides additional shade and sun protection for the centre. Pruning container grown fruit trees follows a similar pattern to ground dwellers, although spatial awareness and physical access should be easier for the container grown specimens. In general terms, efficient pruning techniques require an ability to visualise and work within three dimensional space. Similar to sculpting and other creative pursuits, pruning depends on a number of skills which can be gained through a combination of careful observation, practice, and critical evaluation.