Keen gardeners know that there’s little more satisfying than growing your own plants from seed.

As we come towards the end of winter, propagators and heat mats are a fantastic tool for gardeners looking to protect tender plants, or to get a head-start on their planting for the year ahead. An electric propagator will help to keep your soil at a constant, warm temperature, providing the perfect conditions for young plants to thrive in.

At Keen Gardener, we stock a fantastic range of propagators and heat mats, with both unheated and electric products suitable for greenhouse, out-building and indoor use.

Ensure you get the perfect propagator to suit your requirements with help from the tips in this handy buying guide.

Choosing propagators - things to think about

When choosing a propagator, there are a few key things you need to consider:

What you’re using it for

First, you’ll need to consider what you’re going to be using your propagator for. Is it just for germinating seeds and nurturing your seedlings, or are you wanting to overwinter tender or exotic plants that won’t survive outside or in the greenhouse?

If you are planning on using it for overwintering, you’ll want to think about the height of the propagator – ensure you get something that’s big enough to accommodate the plants you’re planning on putting in it.

Where you’re going to put it

Are you planning on putting it on a windowsill, or is it going out in the greenhouse?

Before purchasing a propagator, think about where you’re going to put it, and carefully measure the space. At Keen Gardener, we offer a wide range of products to suit every space, including models specifically designed to fit on windowsills, and those for greenhouse use.

How much you want to grow

Consider how many seedlings you’re planning on germinating, and how many plants you’re growing. We stock electric propagators in a range of sizes and capacities, from small windowsill units suitable for a handful of seedlings, to expansive greenhouse units suitable for numerous trays and larger pots.

If you’re planning a large project out in the greenhouse, we also offer a range of heat mats, thermostats and soil warming cables – ideal for larger scale propagation.

Choosing a propagator – features to look for

There are a few key features you should look out for when picking a propagator:


The biggest decision you’re going to have to make is whether to go for a heated or unheated propagator. An unheated propagator will help to provide additional protection for greenhouse plants, and a slight boost to soil temperatures, but it is neither as warm, nor as controllable as an electric heated propagator.

Electric, heated propagators can raise and maintain soil temperatures to between 20°C and 25°C – providing the right conditions young plants need to thrive.

Whether you’re planning on growing vegetables, tender plants or perennials, a heated propagator will enable you to start growing earlier, so you benefit from a longer and more productive growing season.

Thermostatic control

Higher end electric propagators will come fitted with a thermostat. This is the best way to control soil temperature, and will provide consistent, accurate conditions required for optimum germination and plant growth.

It’s also possible to buy standalone digital thermostats, that can be retrofitted to existing systems.

Air vents

Propagators typically come fitted with covers and on hot sunny days, this can lead to overheating. Air vents will let hot, moist air escape, protecting young and vulnerable plants from the risk of overheating.

Browse through our full selection of propagators.

How we can help

At Keen Gardener, you will find an excellent selection of the finest propagators and heat mats around, with products to suit every requirement, space and budget, from leading brands like Bio Green, Garland and Stewart.

All products are available at unbeatable prices and come backed up by our Lowest Price Promise.