Robert Mattock's English Roses Grow In Pots
Robert Mattock has been successfully growing roses in pots and containers for nearly four decades. Leading designers use the plants with great aplomb to achieve immediate effect: be that in flower at Chelsea Flower Show, in film and on TV; or green in the gardens of the great and the good. But for the general public setting up home for the first time or those down-sizing to smaller properties, and wanting to create a romantic floriferous, fragrant display of roses on a balcony or terrace, a patio or a back yard it has been a disappointing exercise. Up until now:
Whilst Victorians and Edwardians understood the art of growing English roses in large 50 and even 100 litre pots, it had become virtually a lost art until during the late ‘60s when my late father began to experiment. He was being pressed by the family to produce very large rose trees in flower to make shrubberies out of season for Chelsea Flower Show; what’s more large plants were required but in small (10 litre) pots capable of being packed closely together to make effective natural looking displays.
Father knew very well that ‘budding’ has been the preferred propagation technique of commercial rose growers for the last 150 years or more. Economically just one eye of the desired variety is slipped into a T-shaped cut on an easily established one year old, deep tap rooted, compatible rootstock which, utilising the vigour of the rootstock, grows into a saleable ‘two year old plant’ the following year. The resulting bare-root plant, the industry’s standard product, is well suited to growing-on /establishing in an unrestricted area such as a rose bed or a shrub border.
Conversely the same product is not particularly suited to growing within the confines of a container, pot or a restricted spot in the open ground. The tap root is the problem; it wants to grow far too deep for the size of the pot. For the most part those containerised (as opposed to container grown) rose trees that are sold through garden centres, nurseries, web sites and the like are deep tap rooted plants. Most often the plants have potted into containers that by their very dimensions, restrict extension of the tap root. Moreover they are potted using cheap soft loose structured compost that will not promote robust fibrous root. In effect the customer buys a bare-root plant, root-wrapped and well protected by peat or similar for the couple of years it takes for it to realise that it cannot grow out through the bottom of the pot and therefore dies.
The break through came when my late father the family’s specialist grower realised that to achieve aerial growth of the quality and stature he required, he needed to treat the rose tree as two plants, the arial part and the understock. Great attention had been paid to the arial part by the development of new colours, healthier growth etc., but little or nothing done to the understock.
To contain the vigour of the rootstock he realised that he would have to root prune the tap root dramatically so as to radically alter the pattern of subterranean growth.
Root pruning he knew was indispensable to initiating the shape and form of the extensive robust fibrous or adventitious root system he needed to achieve the consistent high uptake of water and nutrient that the English roses would require to produce high premium quality growth, foliage and flower. In effect my father bonsai-ed the understock.
But initiating the fibrous root system he knew was not enough. The traditional soft structured peat based composts neither supported nor promoted extensive robust fibrous roots minus a stabilising tap root. As a consequence Robert Mattock senior had little option but to develop a robust soil based compost to perfect his growing technique. The exact formula remains a family secret.
In summary the technique for growing high quality english roses in pots:
1. Root prune by cutting back the tap-root.
2. Establish the plant in our special compost.
3. Irrigate constantly from the bottom during the growing season.
4. Re-pot every two years.