Even the most reluctant gardener can transform a bare balcony into a vibrant oasis
This column has heard from a reader who is a keen gardener, and who is at her wits' end at the state of the balcony on her daughter's new apartment. Mother helped to plan and plant up the balcony in question, but daughter has been delinquent, and the containers have all gone to pot.
Alas, we can do nothing to resolve this mother-daughter-balcony triangle, except to point out that for some people, a love of gardening develops later in life, or not at all. It can't be forced. When (or if) daughter is ready to garden, she's blessed with a caring and knowledgeable mother to help her. In the meantime, the two of them might just leave the balcony where it is, and go elsewhere to bond over a nice cup of tea.
But for other people, who are at the gardening stage of life, a balcony may present quite a challenge. Living aloft on the side of a building can be stressful for plants. The higher the balcony, the more weather there is. Powerful winds can shred leaves and slow down growth, and are as effective as heat at drying out foliage and compost. If the building is by the sea, plants are at the mercy of salty breezes, which can desiccate or burn. Light conditions on balconies are sometimes extreme: depending on the aspect, the space might be subject to full sun or deep shadow, or a mixture of both.
All of the above may sound daunting, but really, it shouldn't be. All that is needed is to observe the light and weather on your balcony, improve the conditions if possible, and then get on with choosing suitable plants and containers.
LIGHT, SHELTER AND SUPPORT
If the area is shady, or if the sun hits only a part of it, it may be possible to paint the walls white to reflect light more evenly. And if there is a overhanging balcony above, consider painting its underside also. Wind is best dealt with by erecting panels of a material that will diffuse rather than block it, as the latter approach can cause angry and damaging gusts. Choose trellis (with the smallest possible grid), steel mesh, woven willow panels, netting or fabric. Fix it securely. I can't emphasise that enough, as anything that falls from a balcony can be a lethal missile. So, let's hear it again: fix it securely. While you've got the rawl plugs and drill out, consider attaching trellis or a grid to the walls, so that plants can climb upwards, and pots can be attached at different levels. If the space allows, add a couple of hooks for hanging baskets - but keep these well out of the way of human heads. A smack on the forehead from a full hanging basket is no joke.
Let's stay with the health and safety theme for just another paragraph. Some balconies are sturdily built, and can take the weight of an elephant. Others are much slighter fabrications. If you plan on having more that a lightweight pot or two, ask a structural engineer to assess the load-bearing capabilities of your space.
CONTAINERS AND COMPOST
If weight needs to be curtailed, avoid heavy planters made from terracotta or stone composites. Choose materials such as plastic, resin, timber, wicker and lightweight metal. If your balcony is robustly constructed, and is large enough, you can build a raised bed along one side, giving you a miniature garden. Plants fare better with the greater volume of soil or compost, as it dries out less quickly. Just be sure that there are drainage holes for water to exit safely. Make the side of the bed deep enough to sit on, or so that it doubles as a shelf or table.
Where weight is an issue, use a soil-less planting medium. Peat-based compost is lightweight, but dries out quickly. Add water-retaining gel granules to improve its moisture-holding capabilities. Environmentally concerned gardeners, of course, use peat-free products. They're more expensive, but are made from composted waste (a renewable resource), rather than from our bogs. Where you don't have to watch your balcony's weight, a soil-based compost, such as John Innes (number 2 or 3) is preferable if the plants are going to be in the containers for more than a year.
If containers are deep, fill up the bases with something other than compost to save expense, and to help with drainage: use bits of polystyrene, or (as a friend of mine suggests) old plastic drinks bottles.
Balcony gardens need daily watering during the growing season, so consider installing an irrigation system if you're not home every day or are a little casual. Aim to keep the compost slightly damp all through the container, but not soaking. Mulch the surface with grit or decorative stones to prevent it from drying out. Terracotta pots lose moisture quickly by evaporation, so can be lined with heavy plastic before filling (an old compost bag is ideal). Containerised plants need feeding more frequently than those in the ground. Potting composts usually contain enough nutrients for about six weeks; feed weekly or fortnightly afterwards, but only while plants are actively growing. Or add a couple of handfuls of pelleted chicken manure when planting, and top dress with another handful every four to six weeks. Deadhead flowering plants regularly, to prevent them setting seed and stopping blooming.
WHAT TO PLANT
Foolproof plants for a balcony include ivy and lesser periwinkle (Vinca minor) for shade, and succulents such as sedum, sempervivum and echeveria for sun. These will tolerate quite a bit of neglect (a weekly visit is adequate) if properly planted and mulched. If you can give your plants more care, and the largest possible containers, then there are hundreds of other choices.
SHADY BALCONY
For a balcony that doesn't get much sun, look for shade-lovers and woodland plants. If wind is a problem, select varieties with small or leathery leaves. The following are just a few species that will tolerate partial or full shade: box, Euonymus fortunei and E. japonicus, fatsia, ferns, hosta, ivy, mint, parsley, lesser periwinkle, Skimmia japonica.
SUNNY BALCONY
Plants with leaves that are small and hard, leathery, succulent or grey are perfect specimens for the sunny balcony, as they withstand high light, wind and drought. Natives of the Mediterranean, Australia, New Zealand and South Africa are suitable candidates, as are seaside plants, and the tougher grasses such as Festuca glauca, Stipa and Carex. The list is almost endless, but here are a few: agapanthus, agave and other succulents, cistus, Convolvulus sabatius, cordyline, Fuchsia magellanica, griselinia, hebe, juniper, Mediterranean herbs, olearia, olive, phormium, pine (small varieties), pittosporum, Yucca gloriosa and Y. filimentosa.