Fertometer

Push it into the pot and a light tells you whether there is still enough nutrient in the soil. Made for house and patio plants.

The Fertometer is for anyone with potted plants who does not want to guess when to feed. A pot holds only a limited amount of soil, and the fertiliser in it runs out faster than most people expect. This meter turns that into simple advice via a light, with no numbers to interpret.

What it measures, and what you can read from it

Under the hood the Fertometer measures electrical conductivity in the soil. The more dissolved fertiliser present, the better the soil conducts. That conductivity is translated into feeding advice.

Two things are worth knowing before you rely on that light.

Conductivity does not distinguish between salts. Nitrogen, potassium and calcium from your fertiliser conduct, but so do sodium and chloride from hard tap water, and those are not nutrient to the plant. In a pot watered with hard water the meter can therefore read higher than the actual nutrient reserve justifies.

Conductivity says nothing about ratio. A pot can hold plenty of nutrient overall and still be short of one element. The meter sees total quantity, not composition.

What it does do well is exactly what it is for: showing whether there is anything left in the pot or whether your reserve is spent. And that is precisely where most potted plants get into trouble. Not through a wrong ratio, but because there is simply nothing left.

If you grow hydroponically or in coco and want to steer in tenths, an EC meter giving a numeric value suits you better. For house plants, balcony plants and the vegetable garden, this is exactly enough.

Technical Specifications:

• Measures: electrical conductivity in potting soil, translated into feeding advice
• Display: via a light, no numeric value
• Use: potted plants indoors and out, and the vegetable garden
• Operation: push into the soil and read

Frequently asked questions

Does it measure pH?
No, nutrient level only. For acidity in a medium you need a pH meter with a suitable tip.

Why a light instead of a number?
Because the advice matters more than the figure for anyone not following a feed schedule. If you want a number to steer on, look at an EC meter.

Does it work in coco or rockwool?
It is made for potting soil. In coco and rockwool you normally work with a nutrient solution measured beforehand with an EC meter.

Why does it read high when my plant looks poor?
That can be salt build-up from hard water or from accumulated feed. Flushing with clean water usually deals with it.

How deep should I push it in?
To root level, not just under the surface. The top of the pot reads differently from where the roots are.