A Heat Wave Survival Plan for You and Your Garden .....
ERYNGIUM x zabelii 'Big Blue'
Oh Boy it's been HOT !
We humans and our plants have all been suffering in this heat, so we thought now is the perfect time to share some of our top tips to help you and your plants survive and maybe even thrive in this or any future heat wave.
Firstly, as any gardener will know, you have to take care of yourself whilst you are working outside in the heat.
Secondly, you need to develop a survival plan for your flower borders.
Careful planning will save you both time & money. If you have a border which bakes in the sun then pick plants which enjoy being baked - Bearded Iris, Nerine, Amarine ....
Plants have developed their own survival strategies for dealing with heat, many of these strategies are easy for us to spot - silver leaves which reflect heat, hairy leaves which reduce water evaporation, very narrow or tiny leaves, succulent foliage etc. all of these adaptations are designed to reduce water loss from the plant by decreasing the rate of transpiration.
Transpiration is by definition "The loss of water vapour by plants to the atmosphere. It occurs mainly from the leaves through pores (stomata) whose primary function is gas exchange. The water is replaced by a continuous column of water (and dissolved nutrients) moving upwards from the roots within the xylem vessels. the flow of this column of water is known as the transpiration stream which is maintained by root pressure and a combination of cohesive and adhesive forces in the xylem vessels according to the cohesion-tension theory" Reference - Oxford Dictionary of Biology
Some water and nutrient conserving adaptations are less easy to see but are just as effective, familiar examples might be the deep tap roots of members of the Carrot family or the stem tubers of Potatoes - by choosing plants which have an in-built ability to thrive or just survive in the heat we can ensure our flower borders will still be looking good as the mercury within our thermometers nudges its way upwards towards 30oC and occasionally beyond.
Prepare the ground properly before you plant, add plenty of organic matter, well-rotted manure or garden compost, during spring or autumn. This will not only feed your plants, it will improve the soil structure which in turn will help maintain soil moisture. Admittedly some soils are endlessly greedy and it may take years of adding organic matter before you have the soil you desire - mulching is the easiest way to improve a very poor soil. Applying a layer of mulch in the spring when the soil is moist will help prevent water from evaporating from the soil surface later in the year and it will improve your soil structure without you having to do any digging. Be careful not to bury the crowns of your herbaceous perennials with mulch as this may cause some plants to rot.
Don't plant during a heat wave ! Plants which have been grown in pots can be planted at any time of year but ideally wait until there has been a significant amount of rain and remember to soak the root system of the plant prior to planting by dunking it in a bucket of water. Another one of Rosy's top planting tips is to pour a watering can full of water into the planting hole, allow the water to drain away and then plant.
Do keep newly planted plants watered during hot weather - soak the ground well every couple of days, either early in the morning or in the evening when it's cool, until the plants are well established or the weather cools down and it rains - don't sprinkle the water on the leaves in hot weather as this will scorch the foliage.
Be prepared for a hosepipe ban by installing rainwater butts - check your local water supplier's website for current information on hosepipe bans and if a hose pipe ban has been imposed in your area use grey water to keep your pots and planters going. Prioritise plants which won't survive without water don't be tempted to try and water the whole of your borders or grass.
A Few Herbaceous perennials which once established will thrive in a hot and sunny border .