New Place Nurseries and ReduSol
Moving newly potted nursery stock liners from the tightly controlled environment of a propagation unit and into a production glasshouse inevitably subjects the plants to stress.
“It’s vital to relieve plants from stress, especially during establishment, and, for us, the use of a shade coating has become integral to our management,” says Steve Smart, nursery manager responsible for New Place Nurseries’ production units in the Chichester area of West Sussex, in the south of England.
New Place, which became part of the Roundstone Nurseries group in 2013, specialises in the propagation and production of young nursery stock plants – or liners – growing about 1.7 million a year. Around 80% of its 3ha of glasshouses, split between three sites, is treated with ReduSol each year, usually at the end of April or early May, earlier if the spring is shaping up to be particularly warm and sunny.
“Cooling the glasshouses to reduce crop stress is one of three key reasons for using the coating,” says Mr Smart. “It also enables us to scale back on the irrigation we need to apply; and it provides much better summer working conditions for our staff.”
The shading alleviates the risk of water stress and foliar scorching, which in turn accelerates the establishment of newly potted crops. “We grow around 1,000 different lines so having a simple way of providing a well-balanced atmosphere that will suit them all is essential. Without ReduSol, we just wouldn’t be able to grow some of them through the summer,” says Mr Smart.
While it’s obviously crucial that the plug holding the liner doesn’t dry out, Mr Smart says he wants to avoid applying too much water because that can lead to leaching and possibly to root diseases as well. “Once the ReduSol goes on, we see the amount of water applied fall by as much as 20%. And because the more sensitive plants are less stressed, we can manage the irrigation much the same across all the different species we grow.”
New Place pays a lot of attention to the branching structure and strength of its liners as these are the starting point for the quality of finished plant for their grower customers. “That means we trim by machine once a week during the growing season to stimulate side shoots,” says Mr Smart. “That continually re-exposes the lower leaves and, without effective shade, they would be liable to scorch.”
Shade is particularly important for subjects such as camellia, pieris and some light-foliaged varieties of pittosporum during establishment, and also for many golden-leaved plants such as Choisya ternata Sundance. “Choisya is also quite prone to spider mite,” says Mr Smart, “but the cooler conditions generated by the coating helps to slow development of the pest which is controlled by integrated pest management.”
New Place has been using ReduSol for around 10 years, coating the roofs and all but the north-facing walls of the glass. It’s cleaned from the side walls in October, while the roof coating is left to degrade over autumn and winter. “We’ve worked with its manufacturer, Mardenkro, to learn how to get the best from it and tried various dilutions before settling on the 1:8 which gives us the optimum level of shade for our crops – not too heavy but just enough at peak light and temperature levels – for three critical months,” says Mr Smart. “It has proved very consistent in terms of its longevity and predictability.”