Planting Ideas – Informal Planting

The arrangement of plants in a pool is a very personal matter: what appeals to one gardener, may not hold any attraction for another. The visual qualities of water must also be considered, for they can be as important as the plants.

With an informal style of gardening, it is tempting to think that, as the plants do not appear to conform to any set arrangement, it will be easy to make a pleasing display. Nothing could be further from the truth. Creating a successful, well balanced scheme, which can also be managed efficiently, is extremely difficult. The plants have to look cared for, but with no evidence to that effect.

This problem can be eased to some extent by the use of planting baskets, which allow plants that might invade one another’.s territory to be placed cheek by jowl in the knowledge that they will remain more or less where you put them.

The disadvantage is that containers can create rigid formal blocks of plants, so some ingenuity must be used when positioning them, with perhaps occasional underplanting to soften the edges.

When using stiff upright plants, like Schoenoplectus lacustris and Schoenoplectus lacustris tabernaemontani ‘Zebrinus’, there should be no difficulty in accommodating a low growing marginal aquatic in the same basket. Use only one upright and one lower plant per basket. The brooklime (Veronica beccabunga) and water forget-me-not (Myosotis scorpioides) are two of the best for this kind of arrangement. Neither has a root system that is too invasive, so they will not cause any difficulty for the main plant. Take care not to repeat such plantings throughout the pool margin, otherwise the effect will appear very formal.

 

A SUMMER WATER FEATURE

One of the first points to accept is that the water garden is predominantly a summer feature in terms of flowering and interesting foliage. The informal arrangement depends heavily on planting. The placid stillness of the water during winter is rarely as effective, or important, as in a formal pool, where it may be contrived as a major garden focal point. Therefore, when creating your scheme, you should take into account the fact that, while there are a few early flowering species of aquatic plant, for the most part it will be mid-summer before you see anything resembling a good show.

Arrange the plants to account for their differences in flowering period so that adjoining groups blossom at the same time. Cotton grass (Eriophorum angustifolium) makes a pleasing picture when planted alongside the pretty water forget-me-not (Myosotis scorpioides), while the pickerel (Pontederia cordata) is a natural companion for the flowering rush (Butomus umbellatus). In the spring, place the bog bean (Menyanthes trifoliata) with the common marsh marigold (Caltha palustris), and allow the bright, gold and green, sword-like foliage of Iris pseudacorus ‘Variegata’ to contrast with the glossy evergreen leaves and white sail-like spathes of the bog arum (Calla palustris).

 

CREATING A THEME

To most water gardeners, an informal planting suggests a cottage-garden look, where foliage and flowers mix in a tangled, but controlled, manner. The marginal shelves of the pool appear rather like a small version of a herbaceous border, which may run into the larger herbaceous bed of the bog garden. In a cottage-garden setting, this is obviously the correct thing to do, for this form of gardening is very much about growing a wide range of plants in visual harmony. However, if your garden is not of this tradition, being simply informal, consider theming your planting arrangements.

One of the most pleasing themes is based on the use of pinks and white. Select a bright red waterlily, such as ‘.Firecrest’, as a centre-piece and complement it in the deeper part of the pool with the vanilla-scented, long flowering white water hawthorn (Aponogeton distachyos). In fact, you can use two or three groups of aponogeton around the waterlily in a large pool. Clear water around these deep-water aquatics is essential for the best effect, so do not be tempted to introduce any floating plants.

For the margins use Houttuynia cordata with its purplish foliage and white flowers, the plum-coloured Iris versicolor ‘Kermesina’, silvery-white Caltha leptosepala and pink-flowered Butomus umbellatus. These can all be supplemented with leafy reeds and rushes.

The marginal plantings can be extended into the bog garden, taking the colour theme with them. Deep carmine Primula pulverulenta and selected pink-flowered forms of candelabra primulas, along with the stately P. japonica ‘Postford White’, make lovely combinations, all flowering at the same time. They will look a little untidy later on, so distract the eye, perhaps with Aruncus sylvestris and Astilbe ‘White Gloria’, both of which have splendid feathery creamy or white blossoms in spires above handsome deeply cut foliage.

Apart from the obvious contrasts and complements that any skilled gardener makes when choosing plants, in a water garden an additional consideration is finding a means of disguising the structure of the feature. The edges will demand particular attention, so any arrangement must include plants that will conceal the pond materials and any containers.

If done sensitively, this can improve the whole display, but if done without care, the planting may detract considerably from it. Where associated plantings seem to be either inappropriate or impractical in the same container, make liberal use of creeping Jenny (Lysimachia nummularia), pushing short stern cuttings into the tops of the containers and allowing the bright green foliage to cascade all around. This adaptable plant is equally at home when used to form a carpet among plants in the bog garden. Its very modest rooting system and abundant, well behaved foliage are perfect.

The apparent rough and tumble of what most gardeners perceive as being the typical domestic garden pond does not suit everybody, especially if the garden is laid out in a formal style. In consequence, fewer plants may be used because open water, or a moving water feature, is a more important element in the design. In this situation, the correct selection and positioning of the plants are often even more critical than in a loose, tangled informal gathering.