As a modern specialist nursery concentrating on the UK market it is important that we home produce the vast majority of plants that we grow and sell from our nursery. We grow on 2 acres of ground made up of 2 fields – the Old Field (which came first) and the New Field (which came second!).
Home Grown
We produce more than 90% of our plants here on the nursery – producing them either from seed, cuttings or from mother stock on the nursery or in the garden. Not only is this important to keep our plants true to name it helps us control our environmental impact in terms of carbon footprint and biosecurity. We do buy a limited number of plants, including young starter or liner plants, from other well respected UK based nurseries in order to bulk stock or to obtain new lines, but have not bought plants from outside of the UK for some years.
Hardy Plants grown for the UK climate.
In both our growing fields, plants are grown with minimal protection as we aim to produce good quality healthy plants which will perform long term for our customers. We do not grow for an instant effect preferring to concentrate on supplying plants that will grow successfully when planted in their new homes.
Peat Free Growing for over 25 years.
We have grown in peat free composts for over twenty five years. Our current peat free mix is supplied by Melcourt and is based on their Sylvamix which contains no pesticides but does contain a balanced long term slow release fertiliser to ensure good growth for the young plants while in pots. We use a specially formulated potting bark as a topping for all of our plants, which significantly reduces the ability of weeds to germinate as well as helping to reduce the frequency of irrigation.
Plant Mileage
While plants sourced from outside of the UK will have necessarily travelled perhaps hundreds of miles before reaching our gardens, plants produced at home will have scarcely travelled more than a few hundred metres before being dispatched to their new homes. For example Melica uniflora albida is a very pretty, and very durable, native grass that revels in dry and shady conditions. Seed is collected from plants growing in the garden. The seed is then sown, pricked out and grown on – all within a hundred metres or so of the original seed bearing plants.
Growing from Seed
Though we do on occasion need to purchase seed from other companies anemanthele, nassella, calamagrostis, carex, phlomis and scabious are a few that now come primarily from our own seed. The ever popular white flowered Libertia grandiflora is another that is raised from home produced seed – collected from the Dry Meadow in the garden.
Growing from Cuttings
The majority of our range comes from seed or division but there are a number of perennials such as nepeta, aster, eupatorium and salvia that we produce from cuttings taken mostly during the spring.
Growing from Division
Possibly we produce more plants by division than from either seed or cuttings. This, in part at least, is due to many of the plants in our range being cultivars or selected forms and so cannot be produced true from seed. In addition grasses do not come from cuttings as do perennials and most other plants.
Carex divulsa is a very effective UK native sedge whose demand continues to increase as we come to recognise the value that many of our native plants can bring to our gardens. Although we produce some from seed most of our plants now come from division of open ground stock. There is no doubting the value of open ground production for producing good plants with healthy root systems.
Calamagrostis Karl Foerster is deservedly popular for its upright habit and relatively early flowering nature – and open ground production helps up keep up with a seemingly ever greater demand. It was one of the first open ground plants we trialled and were quickly impressed with the increase in bulk and root system. Plants are now lifted from their open ground bed, split and potted into modules, and then moved into their final pots once sufficiently rooted.
Square versus Round
We are in the process of changing over from 2 litre round pots to 2 litre square pots. Although individually the difference is not that noticeable, these reusable and recyclable square pots allow us to make better use of space in our growing fields – as we get more ‘square’ than we can ’round’ in a given space. Apart from allowing us to grow more plants the absence of a gap between the individual pots means less water is wasted – and there is much less chance of weeds germinating between the pots as there is no space for them to do so.
If that were not enough our plants seem to grow exceptionally well in the ‘squares’. We are not quite sure why but we are very happy that they do!
Control of Pests
No chemically based insecticides are used in our composts as we now rely primarily on nematodes and bioinsecticides to control soil pests such as vine weevil and slugs. While this environmentally sensitive approach has proved to be very effective in practice, it is no longer possible to guarantee that every plant will be 100% free of all pests, though every effort is made to check and re-check our plants before dispatch. In addition the lack of chemicals in our compost mix allows other non harmful insects, such as millipedes for example, to be present in the rootball. These do no harm to the plants but seem to enjoy the decomposing bark that makes up a large part of our compost.
Apart from all the other advantages of home production growing the number of plants that we do we have been in a position to spot a number of variations that have, once trialled and properly evaluated, become new Knoll Gardens selections – with a strong emphasis on plants that are suitable for our UK gardens. Over the years we have released a number of new plants which you can see on our Plant Introductions from Knoll Gardens gallery.
