Overwintering Pelargoniums: Tips and Technologies for Extra Winter Pelargonium Protection.

In this post (from winter 2023) we will be sharing some hints and tips with you of how to help protect your plants over winter - . Please note this blog does contain affiliate links. While we only recommend products that we believe in, we may earn a commission from any purchases you make.

With the weather forecast predicting yet more colder weather, even another Beast from the East, I thought I would share how we protect our plants. 

The main photo shows my favourite P. Ardens frozen solid in its pot following a heater failure and it completely died off - since this happened we have stepped up our winter protection tactics and wanted to share some tips and technologies we have used.

Remember Pelargoniums need to be kept frost free to survive the winter, and ideally in a greenhouse where temperatures can be kept above 5°C.

 

Horticultural Fleece

In addition to lining our growing spaces with bubble wrap, we also use horticultural fleece. Fleece provides a bit of added protection to your plants and we have used it for years. Laying it over the plants creates a microclimate beneath it which will help maintain the temperature a little warmer than the rest of the greenhouse. 

We use fleece to cover our plants most nights when the temperature is particularly low and we always put it on towards the end of the day while there is still daylight and warmth around to trap that within it.

Having our plants fleeced saved a lot of them when our heater failed and the temperature inside the greenhouse dipped to -4°C.  We still lost a lot but we are certain we would have lost them all if we hadn't had the fleece - My P. Ardens was not under fleece that night :-(

After that night we went a little extreme on the fleece everywhere!!  Fleece similar to the type we use is available on Amazon:  https://amzn.to/45erJmb 

 

Greenhouse Heaters

Whatever type of heater you are looking for you just need to make sure it is a reliable one and it will cope with the extreme temperatures we have been seeing more recently.

For our smaller propagation greenhouse we use an electric heater with a built in thermostat.  We use the Elite Hotbox fan heater as this helps move the heat around and also has an thermostat to control the temperature - we also use it just as a fan in the summer to help circulate the air and cool the growing space.

If you use an electric heater but it does not have a thermostat I would recommend an additional Digital Temperature controller that could help control the temperature - and your electric bills!

For our larger growing spaces we use propane heaters. We use Shilton greenhouse heaters as these have in again these have inbuilt thermostats to help control the temperature, and help with those energy costs!!  

 

 

Thermometers

A good high/low thermometer will allow you to monitor the temperature of your greenhouse to try and make sure you can do the best you can to protect your plants. We use some of these in our growing spaces and it has helped us keep an eye on things over the years. 

      

With this winter though, seeing temperatures drop to -10°C some nights we needed more, we needed the ability to be alerted should the temperature drop below that the heaters could cope with or just if the heater had failed.  We installed the Govee Wifi Thermometer.  This has been a real changer for us!

I have an app on my phone so I am able to check in on the temperature without having to get up in the middle of the night and head into the greenhouse to physically check.  It also means I receive an alert to tell me if the temperature falls below a preset level so I have time to go down and check out the problem.

One night the gas ran out sooner than expected and so the temperature started dropping, but I was able to get there and sort the issue before it dropped below freezing!

The Govee does need wifi and we didn't have internet in the greenhouses so have used a 4G Wifi router, similar to this one - D-Link 4G Router (ours is an old one we had) and a pay as you go SIM from EE. They are usually battery operated so will need charging up, but we usually hook it up to a battery pack.

Hopefully seeing what we use to get our plants through the winter will help give you some ideas of how you can better protect yours!

Don't forget you should only plant out Pelargoniums in the UK after all risk of frost has past - traditionally this is after the Whitsun week.

Happy growing!