HEATED PROPAGATORS PUT TO THE TEST

Rachel Graham compared three heated propagators to see how design, heat and humidity affect early sowing in the depths of winter

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In the interests of science – and because it was cold, dark and I don't have electricity in the polytunnel – I sowed radish, beet and chard into three heated propagators to see how they behaved in real winter conditions. The results were fast, chaotic, and surprisingly revealing.

PROPAGATORS TESTED

A - Vitapod Small: Premium thermostatic propagator with generous lid height and stable heat. (Around £179)

B - Growarm 100 Heated Starter Tray: Budget fixed-temperature unit; shallow lid, takes two half-trays. (£23–25),

C- Garland Super 7 Windowsill Propagator: Mid-range compact propagator designed for small spaces. (£39–50).

THE SETUP

December is not a sensible time to sow anything indoors unless you're prepared to watch your seedlings like an anxious mother hen. But enthusiasm won, and with no power in the polytunnel I had no choice, so everything had to happen on a dining table in my very cold house!

To keep things fair, I sowed radish, beetroot and chard into John Innes seed compost, using:

• Compost directly in trays

• Plastic cell trays in trays

• Plastic cells without trays

• Fibre/card cells in trays

• Fibre/card cells without trays

In two of the three propagators this made little difference – but the Vitapod exposed a quirk in fibre pots that we'll come to. All trays were fairly densely sown. This wasn’t about raising perfect plants, but comparing germination and heat behaviour.