Grass Clippings

Around the grounds

Finally, there is a feeling of hope in the air. I’m side stepping any Prime Minister announcements planned next week but I am basing my optimism on the great thaw that has occurred with the rise in temperatures in the south east in the last week.
January has been grim month with torrential rain then leading into a cold snap which froze SW15 into a grassy-covered ice cube for the last few weeks. All project work has had to be stopped and we resorted to Plan B in terms of woodland works and working on the periphery of sports areas for fear of not damaging the turf areas while in a cold storage. This week the Padel court contractors have returned to pick up where they left off, with the construction of the subbase for the new courts. We have a company on site who are installing pipe work for infrastructure developments across the golf course west to east to link up electrical and communications lines, so we have a joined-up approach for the future.
On the course, the greenkeeping team making headway in cutting surfaces when and where they can. To do so in the past few months would have created more damage than would have been productive so now is an opportunity to start to shape up areas in anticipation for spring.
Within grounds, this week the team are continuing the install of drainage on the croquet lawns and cleaning tennis courts. Our gardeners have been using all the Yorkshire limestone rock removed from the mini courts area to build a new rockery behind the 18th green and the piazza. The team are busy and we are all hoping that spring arrives early so we can get the planned renovations under way and completed before the return of Members so the course, courts and lawns are ready for happier days to come at the end of lockdown.

The Big Freeze – tips for gardeners

The harsh freezing winds over the last few weeks will have damaged many soft tender plant tissues. Plants can survive frosts by several mechanisms. Sometimes bark can insulate the living water-conductive tissues in the same way that water pipes are lagged to prevent water freezing within cells. Other plants accumulate materials, such as certain sugars and amino acids for example, that act as anti-freeze lowering the freezing point of cell contents – shortening autumn days induce this. A more effective mechanism is the ability of some plants to allow their cell contents to ‘superfreeze’ where the cell contents remain liquid even though below freezing point. To do this, plants must experience several days of cold weather before the freeze and this explains why even hardy plants can be damaged by a sudden autumn frost. In very severe climates such as within the arctic circle native trees remove water from their cells, tolerating the dehydration of the cell contents, and place the water between the cells where it can freeze without causing damage. This works where the weather provides a prolonged slow chilling. Sometimes frost damage is apparent almost immediately following freezing. However, this is not always the case and with some plants, particularly woody ones, the damage may take several months to appear.

Look out for the following signs: –

Tender young growth may be damaged by spring frosts, causing scorching and pale brown patches to appear between the leaf veins. This tends to be on the exposed and top edges of the plant e.g. acer and carpenteria
Hard frost in winter can cause the leaves of hardy evergreen plants to be scorched and turn brown, and may eventually lead to the death of the plant, e.g. bay and pittosporum
The foliage of tender perennials e.g. dahlia and canna may be blackened by the first frost of autumn. Stems usually collapse
Spring frosts can damage blossom and young fruits. This may cause a corky layer to form at the flower end of the fruit i.e. apple and damage to blossom may lead to few or no fruits forming
As a result of late spring frosts summer bedding plants and tender vegetables, such as potatoes and tomatoes, may suffer from leaf scorch, browning and even total plant death
Prolonged periods of frost may cause spotting on the leaves of some shrubs such as photinia and garrya
The foliage of certain plants exhibiting early symptoms of frost damage appears water-soaked and dark-green, turning black in time
Ground frost occurs when the temperature of the ground falls below freezing point (0ºC/32ºF) and air frost occurs when the temperature of the air falls below freezing point. Plant cells can be damaged or even destroyed by frost. Repeated freezing and thawing, or very rapid thawing can be particularly damaging to plants. Once the temperature has fallen below freezing, a strong wind can make a frost more damaging. Cold winds remove moisture from evergreen foliage more quickly than it can be replenished by the roots; this can cause leaf browning particularly at the tips and margins. Tender plants survive the winter better when they are planted in a sheltered sunny position. This is because new wood is ripened by the sun accumulating more carbohydrates during the growing season, making it more frost resistant. Newly planted, young plants can be more susceptible to frost damage than fully established specimens. Cold air naturally flows downwards on sloping ground, collecting at the lowest point or against a barrier, this is known as a ‘frost pocket’.

Prevention of damage

There are a number of ways to keep your plants safe during cold weather:-
Choose plants that are reliably hardy and suited to your growing conditions. The RHS Plant Selector can help you choose hardy plants
Slightly tender plants should be grown in a warm sunny spot, e.g. against a south-facing wall, which will provide some extra warmth and winter protection
Cover plants with a double layer of horticultural fleece or other suitable protection when frost is forecast
Mulch the root area of evergreens, conifers, tender shrubs and tender perennials with a thick layer of organic matter to prevent the ground becoming frozen
Move container-grown plants to a sheltered part of the garden in cold weather and provide some extra protection by wrapping the pot in bubble wrap
Leave the previous seasons’ growth on more tender plants until spring, for example penstemon, as this provides valuable frost protection during the winter
Tender plants can be lifted or moved to a more sheltered position or greenhouse. If this is not practical then protect them by wrapping examples include bananas and tree ferns
Lift tender perennials such as dahlias, cannas, pelargoniums and fuchsias before the first frosts
Avoid applying nitrogen-rich fertilisers late in the season as they stimulate soft, sappy growth which is especially vulnerable to frost damage
Plants exposed to early morning sun may thaw too rapidly after a frost, causing damage to flowers and young growth. Camellia and magnolia flowers in particular can be ruined by a single frost

Treatment of damage

As most gardeners will testify, it is easy to be caught out by frost. And sometimes frost damage is simply unavoidable. When damaged has occurred, what should be done?
If no more frost is expected, prune out damaged growth, cutting to an undamaged sideshoot or bud
After pruning, apply a top dressing of a general-purpose fertiliser, such as Growmore at the manufacturer’s recommended rate, to encourage strong re-growth
If a fence or hedge is causing a ‘frost pocket’ consider creating a gap, or remove some of the lower growth to improve cold air drainage
Frost may lift newly-planted shrubs out of the ground, so check and re-firm the ground around them
In gardens exposed to cold winds, consider creating more shelter by planting a shelterbelt
Even though the foliage of dahlias and cannas has been blackened by frost the roots are alive and can still be protected or lifted and stored

Peter Bradburn, Course and Grounds Manager