Plant Selection
To some degree everyone, who buys a new plant for their garden will have a criterion. It may be as simple as just liking the colour or highly fragrant. More experienced gardeners will be thinking about their growing conditions such as dry or wet soil. Here at Whatton House we have a number of things to consider before investing in a new plant for the garden.
As a starting point we can look to the RHS (Royal Horticultural Society) who give worthy plants an AGM (Award of Garden Merit). To earn an AGM a plant will have gone through a trial typically lasting three-four years. If a trial is not feasible a group of experts come together for a roundtable discussion. A plant must have the following to earn an AGM: Excellent for ordinary use in appropriate conditions, Available, Good constitution, Essentially stable in form and colour, Reasonably resistant to pests and diseases. Consequently if a plant has an AGM we can be reasonably confident it is one of the best of its type and we will often chose it over something similar that does not meet the same standard. There are however some plants that may have not been included in the latest plant trial of a particular genus or species. This might be because it has only been introduced to cultivation and was not around when the trail started. Therefore, there are some very good plants out there that have yet to receive an AGM. There is of course an element of subjectiveness, and we use the AGM as a guide rather than an absolute.
The growing conditions at Whatton House are a major factor in what we chose to grow. The soil is predominantly clay and can get rather wet in winter. So generally Mediterranean plants that require good drainage are generally avoided, however plants that can handle summer drought are highly sought after. The P.H. of the soil is variable across the 15 acres, there are patches that are more acidic and consequently that is where you will find the Rhododendrons. Other areas are neutral to alkaline and lend them selves more to the Philadelphus. The ongoing maintenance of a plant is another factor. Does it require regular pruning, and how technical and time consuming is that pruning? Hybrid Tea and Floribunda roses require more attentive pruning than shrub roses, thus we tend to choose the shrub roses for ease of maintenance. Then there is flowering time. The garden is open to the public March to the end of September. Therefore, there is little point investing in plants that perform out of this timeframe. The garden is at its peak in Late Spring- Early Summer but we would like more colour for Mid-Late Summer. Plants that flower for as long as possible such as Aster × frikartii 'Mönch' are highly valued for keeping an area colourful.
We are not a botanic garden so we are not overly concerned about rarity or plants that could be described as ‘botanically interesting only’. What we are concerned about is a plants overall performance. Will it grow well here? Does it give a long season of interest or multiple seasons such as a tree with spring blossom and autumn foliage? Can it deliver with the minimum amount of intervention such as dead heading? Will it serve a functional purpose such as good ground cover to help cut down on weeding, or will it act as a wind break to provide more shelter?
Something else worth considering is how a plant fits in with the style and history of the garden. To a degree it is more how the plants are arranged rather than what is used that is important. Overly tropical and architectural plants are probably best kept to a minimum as they do not really fit the late Victorian to Edwardian history and style. The Philadelphus collection however does fit in with the historical time frame of the garden and have grown well at Whatton for decades. Some are very rare in cultivation and to this end we are doing our bit to work with Plant Heritage to stop this particular group of plants going extinct. We may also apply to be a Plant Guardian for Deutzia ‘Joconde’ which we have a very fine specimen of. It does happen to have an AGM and in full flower you will apricate why. At present there is only one supplier of it in the country, so it is both a good performer and rare.
As you can see there several things to consider before we invest in new planting. This all feeds back into making the garden more sustainable whilst improving its overall presentation.
William Stanger. M.A. of Four Winds Horticulture is a local Garden Consultant. He is advising Whatton House on the garden’s regeneration. He has worked at various gardens in the U.K and New Zealand.