How to prepare a tomato garden bed

  • In a couple of weeks’ time we’re going to plant out our tomato plants, so now’s the time to prepare the garden bed.
  • It’s a good idea to test the pH level (acidity or alkalinity) of your soil with a pH soil testing kit, available at garden centres and hardware stores.
  • To test the soil, take a scoop from 5 centimetres beneath the soil surface. Dry it out and take the chunky pieces out. Put 1 centimetre of soil into the testing tube, add the suggested amount of barium sulphate, then fill to 2.5 centimetres with the pH testing solution. Give it a good shake and leave for 10 minutes. Check out the chart supplied – dark red means Very Acid and dark green means Alkaline.
  • Ideally most garden beds will be between 5.5 and 7 on the pH scale. But every vegetable prefers a different pH level, so check the chart included.
  • Tomatoes need loads of calcium in the soil to grow well. So if your pH reading is Acid or Very Acid you’ll need to add Garden Lime to your bed. If your pH reading is Neutral or Alkaline, then you should add Gypsum (calcium sulphate). Gypsum adds calcium to the soil but doesn’t affect the pH level. Gypsum also opens the particles in the soil providing better drainage and therefore works well on clay soils.
  • Rob’s soil is Neutral, around 7 on the pH scale, and tomatoes like it from 5.5 – 7.5, so he’s going to add gypsum and also compost to his bed to lower the alkalinity.


Camera: Jarod Murray
Editor: Thomas Asche
Production equipment and post-production services provided by The Black Forest Breathes