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Best heated propagators
We've tested heated propagators to give you a head start on sowing seeds and taking cuttings while it's chilly outside.
Ceri studied horticulture at the University of Reading and RHS Wisley. She edits Which? Gardening magazine and our online gardening content.
Heated propagators are great for improving the germination rate of your seeds and helping you get cuttings to root.
They’re cheap to run, and you don’t need a lot of space for them as there are plenty that will fit on a windowsill.
Our tests reveal the best ones to go for, and we give you a few tips on using them.
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Best heated propagators
When testing heated propagators we looked for the models that regulated the temperature well, had good ventilation and would work equally well for cuttings and seeds.
One of our Best Buys worked well for seedlings and cuttings and had great ventilation. Another gave great options for seed sowing.
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| Product name | Dimensions L x W x H (incl. lid) cm | Overall Score | Instructions | Suitable for seeds and cuttings | Temperature - how well regulated | Temperature - eveness | Germination rate | Ventilation |
|---|---|---|---|---|---|---|---|---|
| EarlyGrow Heated 3-Bay Windowsill Propagator | Sign up to reveal Get instant access to this and all our scores and recommendations. Unlock tableFirst month £5, then £11.99 per month, cancel at any time Already a member? Log in | |||||||
| EarlyGrow Heated Propagator, Medium | ||||||||
| Garland One Top Electric Propagator | ||||||||
| Garland Super 7 Electric Windowsill Propagator | ||||||||
| Garland Trio Top Electric Windowsill Propagator | ||||||||
| Sankey Electric Propagator 38cm Growarm 100 Kit | ||||||||
| Selections Jumbo Windowsill Heated Plant Propagator (80cm) | ||||||||
| Stewart 38cm Premium Thermostatic Control Electric Propagator | ||||||||
| Stewart 38cm Essentials Electric Propagator | ||||||||
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Get instant access to this and all our scores and recommendations.
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Ignores price and is based on: Instructions, 5%; suitability for seeds and cuttings, 10%; temperature regulation, 25%; temperature eveness, 25%, germination, 20%, ventilation 15%
How to get the best from your heated propagator
Thermostats
- Propagators can have a fixed thermostat which shuts off the heat at a fixed temperature, or no thermostat so the heating element stays on constantly. With no thermostat they heat the compost to around 8-10C above the ambient temperature and can overheat on a sunny windowsill or in very warm conditions.
- If your propagator has no thermostat, keep an eye on it and remove the lid, move it, or turn it off if it gets too hot.
Using your propagator
- Sow seeds and put cuttings into separate trays or pots and put these into the propagator. Never fill the propagator base with compost.
- Keeping the compost evenly moist helps to maintain a more even temperature in different parts of the propagator.
- Humidity can help with germination, but excessive condensation can promote mould growth once seeds start to germinate. Use the lid ventilation to minimise condensation, especially once germination begins, and shake water out of the lids periodically. Take them off altogether if necessary.
- Once all the seeds in a tray or pot have germinated, move them off the heat so they don’t grow too tall and leggy.
- If you take a lot of cuttings, check the lid height is sufficient to fit the sort of material you take, or you will need to cover taller cuttings with plastic bags and just use the heated base.
Take cuttings with the best secateurs