I’ve been asked a lot about my approach to sowing seeds, and it seems an opportune time to write about that. Though some seeds are best started off in pots (tomatoes, aubergines, celery), the majority of my seed sowing is done in module trays.

A module tray is a tray with individual compartments or modules in it. A decent-size tray will measure 335 x 515mm and have between 80 and 150 modules. They are made from tough plastic, so they can be used again and again. The beauty of a module tray is that the roots of seedlings are kept apart, which means you don’t upset them when you are transplanting them.

Before you fill the tray with compost, it’s important to work with the compost a little first. Break up any larger clumps – this is important, because smaller seeds might fall down through the cracks and fail to germinate because they’re too deep in the compost. I start by completely overfilling the tray with compost and working it in to the modules with my hands. Banging the tray against the bench a few times will help the compost to settle down in to the container. Overfill it again. Then use a flat stick or piece of timber to “slice” the excess compost off the top of the tray, leaving a flat, clean surface on the module tray.

Divots

Before sowing the seeds I make a “divot” in each module with my fingers. This is the little recess in the compost in to which you will drop the seed. I usually use two fingers from each hand to do four modules at a time to speed things up. How deep you make the divot depends on how deep the seeds need to be. A good rule of thumb is that you sow the seed roughly twice as deep as the seed’s size. So, a tiny lettuce seed is almost on top of the surface, while a larger seed, like a squash or pumpkin, would be much deeper.

Depending on the size of the seed, you can either pick one up and drop it into the divot, or use a plant label to move it off the palm of your hand and let it fall into the divot. With most vegetables, you will be sowing one seed per module, but with others (for instance, oriental greens) you might be sowing three to four seeds per module.

Labelling

It’s really important to label the tray. I use white plastic labels and a pencil, so they can be washed off and reused. I always write the name of the veg, the variety and the date it was sown on the label. So, for example: “Beetroot, Detroit Globe, 17/04/17.” That way, if germination is slow you can check how long it was since it was sown.

To cover the seeds, I then overfill the tray with compost again and slice the excess off with my trusty stick, to leave a flat surface. I then bring the trays outside and water them on the ground outside the potting shed. I use a fine mist setting on the hose, but a fine rose on a watering can is just as good.

Check out the videos in the Get Growing section ofgiy.ie to see the seed sowing in action.