Plants are usually selected by 'first impression' on being seen in the plant nursery in a container. Such quick or impulsive purchases can oft 'lead one up the garden path' purely and simply for not being what they seem to be at first sight.

Following on from last month when location and its impact on plant growth was discussed, in the same vein, growth association plays an important factor in the success or otherwise of any design or indeed random planting.

In its simplest terms, growth association is the understanding and therefore uses of plants characteristics to create a garden that will not under 'normal conditions' become overcrowded.

As much as anything else in a garden, plantings that are too close suffer almost immediately owing to competition of water intake, rate of growth, loss of light and the possible spread of pest and disease.

When contemplating the purchase of plant(s) determine in the first place the 'need' for the plant, e.g. function or aesthetics, from this one can then focus on specific plant material to fill the need.

In tandem with the aforementioned point, if plant selection is to be for a mixed bed, consideration should be given to selecting material which will complement surrounding material, this simply means when one plant is not looking good or is not flowering, the adjacent plant should be in bloom or have attractive seed/fruit etc.

The two important characteristics pertaining to growth association are potential height and width of the plant.

Many of our plants grow rapidly during the spring and summer, to the point faster growing plants can 'overcome' slower growing types to the detriment of the latter.

This therefore becomes an important part of the design process, to know your plants habits before you plant.

The area to be planted is also important for the planting to be successful; if planting against a wall or hedge the design should have tall plants to the rear of the bed with other plants cascading down to the front of the bed with low ground covers.

In a free standing bed taller plants should be in the middle with smaller plants again cascading down to the sides of the bed; with this design the beauty of all the plants can then be seen.

Try and avoid creating narrow beds along footpaths or driveways, and aside buildings, they are very difficult to plant and maintain as low maintenance, as plantings invariably outgrow the area too quickly thus requiring immediate pruning which becomes a constant exercise to the detriment of the plant and the design.

In dealing with clients who have this problem, it is obvious that the cost of 'too many plants' coupled with soil and labour was an unnecessary expensive.

Leaf colour, texture and shape are all interesting features to use and indeed highlight in a mixed planting bed, as are flowers, fruit and seed; bark can be an interesting feature but only occurs on a few plants in Bermuda.

Several plant nurseries now stock ornamental grasses, with a range from green variegated white to purple maroon, and even a brown leaved Carex sp.; flower spikes are also unusual and give extended interest to the garden.

Ornamental grasses make a great contrast to any garden bed, but care must be taken as to what 'partners' them with regard to height and width; taller grasses are best planted to the middle of the bed, and surrounded with plants that bloom or have distinct foliage.

Leaf texture and shape are often found in cacti and succulents, plants which are under-used in Bermudas gardens. Many of the Aloes and Agaves show a good depth of colour and leaf shape, with colour ranging from green hues, grey-green to variegated green/white to green/yellow.

In exposed areas many cacti and succulents do relatively well, including Opuntia sp. (Prickly Pear) and Pedilanthus tithymaloides (Slipper plant).

Other plants of interest and worthy of a place in most gardens, would include, Punica granatum (Pomegranite), Alpinia zerumbet (Variegated ginger), Breynia disticha "rosea-picta' (Snow plant), Gaura sp, Pyracantha coccinea (Firethorn), Abelia grandiflora Ed goucher, Brunfelsia pauciflora (Yesterday, To-day and Tomorrow), Grewia occidentalis, Feijoa sellowiana (Pineapple guava), Zamia furfuracea, Phoenix lourei (Pygmy date palm) and not to forget one of my favourites, Senecio confuses (Mexican flame vine).

Many ground cover plants once established spread themselves over a large area of ground, two such examples being Osteospermum 'vars' (African Daisy) and Aptenia cordifolia (Baby Sun Rose).

The extent of their 'spread' should be considered before planting in order to benefit from the weed blanket thus formed; planting centres should be in the range twenty four to thirty inches.

Lantana 'vars', Pentas lanceolata, Rosmarinus sp (Rosemary) and Scuttelaria 'vars' are all what I would term four year perennials, that is they only really look good for up to four years, after that they degenerate.

All these being of a flowering nature from spring to autumn; they must be dead headed to encourage new growth. Being low growing they are best planted in a sunny protected position to the front of the bed, planting centres as for Aptenia.

In passing I would mention three plants which have really done well this spring, the common Pittosporum (Pittosporum tobira), Pride of India (Melia azederach) and Bottlebrush (Callistemon viminalis), the former a large growing shrub and the latter a tall tree and medium sized tree respectively.

A well planted garden is a joy to behold, but in reality 'patience is a virtue' when it comes to achieving the desired effect.