CuCon18 - We're Talking Cucumbers and Plant Care in a Heatwave

These are testing times my gardening friends. We all endured the long dark winter and spring kind of fizzled out until, pow, we hurtled headlong straight into a proper grown up summer.

Every morning for weeks we have had blue sky and ever strengthening sunshine. And it’s playing havoc with my greenhouse and veg.

Each day I am plying my toms, cue and aubergines with gallons of water. The peppers need less as I’ve found they prefer to be grown on the drier side of moist. And that's a sentence you rarely read. I hope.

But there are steps you can take to minimise the impact of a heatwave on plants.

Monitor Greenhouse Temperatures

So, "water to the roots" is obviously a great idea but stop and think about the leaves of your greenhouse plants. They are being cooked. In situ. I’ve been monitoring the thermometer in the greenhouse and temperatures are reaching mid 40s by mid-afternoon. Scorchio. And that results in one big thing - plants switching off.

Photosynthesis Stops

Once a temperature goes above 36C, proteins in the leaves start to breakdown (or ‘denature’ if you are still studying for your A levels) and that switches off photosynthesis. In turn, the little holes in the leaves, the stomata, close to prevent any gas exchange = total ‘no thanks, I’m alright doing nothing for the time being‘ from the leaves. As a result, leaves turn a sickly pale yellow. Phew - that's a Plant Science lecture in a few lines. In other words, to keep plants looking healthy you need to keep temperatures down a bit.

Create Shade

Shade is the key. A simple umbrella, strategically placed, will act as a temporary shade for vulnerable plants. You can buy shade paint to slap over greenhouse windows to create shade and blinds can be installed. Pricey but they look good, especially when rigged up to an automatic system activated by temperature. An automatic opener for your roof vent is a must. Just make sure nothing is obstructing its mechanism. Leaves, moss and algae can accumulate and will stop windows from opening.

Damp Down

Damping down the floor, or splashing water directly onto the greenhouse floor, will raise humidity which will keep plants happy - a great way to ease plants through the hot spell. Moving plants away from the glass will reduce stress. All simple yet effective strategies for keeping cool.

Find all our watering accessories here.

Get a Helping Hand

If you have to go away for a few days, or even a night, you first need to organise a CuCon. That's a Cucumber Conference, obviously. Sit down, get the undivided attention of the neighbour or family member you have decided to bestow this responsibility on and talk them through the tasks. Ensure they ask questions and fully understand. This is important - plants' lives are at stake. Leaves could boil if that umbrella falls or the simplest of tasks - such as opening the door in the morning - fails to be done. Plants will dry out within an hour on a hot day. Only entrust this power to someone who cares, someone who knows how to shoo a young blackbird out of a greenhouse containing cacti and someone who knows when the village show is.

I wouldn’t bother going away to be honest. The weather's good enough here anyway!