Grass Clippings
Finally, nature’s thermostat has gone up a notch and the low morning cloud, which was encroaching in from off the North Sea has now disappeared. This was keeping half of the day in the low twenties, which in real terms meant a lowering of the heat stress of most turf and plant life. A warm spell is predicted which will affect how the turf surfaces react through the next few months.
Soil temperatures have increased dramatically in the last week, and the warming of the top 50mm (four inches) of soil will start to stress the grass in all areas. I have been counting the weeks, before the temperature has reached 30 degrees and I am optimistic that we can retain turf in non-irrigated areas for longer this season.
July and August will be the test to try and keep in all alive and kicking. I only hope that the heat doesn’t damage more trees than last year. A fully grown oak tree is very thirsty! They can use up to 100 gallons (about 378.54 L) of water per day during the growing season. It’s probably a reason why the rough dries out so rapidly on the golf course, as most of the trees have been planted between the holes and so draw moisture out of the ground from the area within the drip line of the canopy.
The tree nurseries that we use to purchase stock have lamented that this winter has been one of the worst for tree losses for several decades. Being a supplier all around the UK, they get a comprehensive picture on how the regions have rebounded since winter. The general view is that species are doing better than others, but concerns are still high on what this summer will do for many vulnerable species. So far, we have been able to manage our irrigation use well this year and the low temperatures and cloud cover has helped with that process.
The calculation we use for estimating water usage is based on ‘ET’. Not the 1980s Spielberg film about the wrinkly alien but ‘evapotranspiration’ which is a simulation of water evaporation from the leaf combined with the amount transpired from the plant. This is measured in millimetres (of loss) which allows us to figure a run time, for irrigation rotary heads to calculate the amount needed to replace ‘ET’ loss. It sounds more complicated than the practice, but it works. This weather favours the tennis courts which are akin to cricket squares in that the relationship with clay content in the court helps to maintain the bounce of the ball. The grass cover supports keeping the clay surface intact and stabilizes the soil, so it doesn’t break up. Water management of grass courts takes experience and practice to master and the nuances of the location and how clay holds on to moisture is sorcery itself.
As previously mentioned in Grass Clippings, many gardeners have noticed that this year has been a good year for the roses, as well as other flowering shrubs. In a Times article last week, Tony Hall, head of temperate collections at the Royal Botanic Gardens in Kew, southwest London, aired his thoughts that gardeners were enjoying record roses because of the long winter and dull spring.
March being, the sixth wettest since records began in 1836, according to the Met Office, helped by cutting back on every rose-lover’s worst nightmare — aphids. Tony added, ‘My own thoughts are that the spring was the coldest we’ve had for some years so the roses had a longer dormant period, meaning they’ve had a much better rest,’ Hall said.
It’s a little counter intuitive but in some cases that trees have suffered more than shrubs this last season. Plants in borders may well have had a better deal compared to trees which are very much more exposed, due to their height and exposure limits. How the soil, at depth, reacts with the water table may well favour or hinder trees in different locations.
Summer is here and al fresco dining season is in the air. Here are a few tips for summer to make sure the garden is looking good for summer visitors.
- Watch the weeds!
Weeds can be inevitable, even in the most well-kept gardens. As the weather gets warmer, the weeds come out, but there are ways of deterring them from growing in your garden.
◊ Applying mulch, which supresses light to weed seeds and also helps to keep moisture where its needed, near the roots.
◊ Weed after it rains when the soil is moist, it so much easier.
◊ Cultivating the top few inches of the soil to break seedlings up before they grow to large.
- Fertilise
There are many types of fertiliser on the market, so make sure to find a fertiliser will work best in your garden. The healthiest gardens use some type of fertiliser because most soil does not provide an adequate amount of nutrients to plants and flowers. A mid-summer application to boost the colour and condition during the hottest months. Liquid feed pots and baskets frequently and do so at the beginning or end of the day to prevent scorch to the plants.
- Watering schedule
The very best time to water plants is in the early morning or late evening, as above for fertilizing, while it is still cool. This will allow the water to run down into the soil and reach the roots of the plant without too much excess water lost to evaporation. When rising kitchen items or cleaning off salad or vegetables, keep a bowel in the sink a when full, nominate a plant or area of the garden to receive a welcome drink. You will be amazed how much water is wasted by indiscriminate use of the kitchen tap.
- Pruning shrubs
Early summer is the time to prune many of the spring-flowering shrubs such as Philadelphus and Weigela. Prune off growth that has just finished flowering down to an outward facing bud, along with any damaged or crossing branches within the shrub, which should be removed either to suitable growth or completely.
- Finish planting annual bedding plants
If you didn’t have time to plant out your tender bedding plants in May, there’s still time to get them into the ground or their new containers as soon as you can in June. Make sure to place them in good light, so they do not become drawn and spindly in the shade.
Throughout summer, regular deadheading will keep them looking fresh and neat and you will quickly realise what brilliant value for money bedding plants are.
Peter Bradburn, Course and Grounds Director