If you are anything like me, you have windowsills full of seed trays or a greenhouse that is starting to become impossible. Germination does seem to have been good this year, if a little erratic and unexpected in terms of timing, and things are looking good. Apart from cosmos. Cosmos usually sprouts like a weed but I have heard a lot of people have had slightly woeful results this year.

Anyway, even if you are a little short of time and a lot short of space, getting seedlings out of seed trays is important. Plants that get ‘checked’ or stopped in their process of growing, can often really struggle long term, so keeping one step ahead is important. Checking can happen because the root system has run out of room in the seed tray, especially if there are a lot of seedlings in the same tray, or because the compost hasn’t got enough nutrition to keep the seedlings growing. Seed compost has very little food in it because the energy needed for germination is held within the seed itself so once the plant get growing it needs more. (This is why I sow sweet peas and the squash in a proper multi-purpose; I know they are going to be in there a while and I am not going to want to pot them up because root disturbance is a bit of a nightmare for then.) If your seedlings are looking even slightly yellow, then they are hungry.

You will need:

• Organic, peat-free compost

• Pots. I use 9cm square pots because they are big enough for a fair bit of growth but I can fit a lot of them in one big tray. Also square pots that fit perfectly together are most efficient in terms of watering and not allowing spaces for slugs to get comfortable in the greenhouse.

• Labels & a pencil/permanent marker.

You can sometimes use your pencil to lift out the seedlings and make the hole in the compost but I had left this phlox a bit long and their roots were a bit big and quite intertwined with each other so I used the bread knife that is kept in the greenhouse for harvesting asparagus.

Fill the pot with compost. Do not tamp down or over-fill at this stage, just get some nice fluffy compost up to the rim. Make a hole in the centre with a pencil or your finger. If the roots on the seedlings are much bigger, it might be easier to put just a layer of compost in the bottom of the pot, hold the seedling at the right level and then gently put compost around it. Definitely don’t try and force the roots downwards into a hole that is too small.

Gently lift (don’t pull) the seedling out of the seed tray. All the advice is to touch the leaves not the stem because a plant can recover if the leaf is damaged, but if the stem is bruised or broken, that is it. Sounds straightforward advice but actually very difficult to follow. You will want to touch the stem because it feels like the most resilient and graspable part of the plant. I’ll let you weigh it up.

If they come up in a clump, separate the seedlings gently. At this stage, they can tolerate some of the roots being broken off and disturbed. Plants that have suffered a bit of root breakage but which then fit perfectly in the potting up pot will do better than those that have had their roots intact but that are then pushed into a too small hole with the roots pointing upwards or generally being squished.

Take a bit of care dropping the seedling in, and then gently firm (do not press) the compost around it.

Label. (Do as I say and not as I do…)

Water from below quite generously. You want the surface of the compost to darken before you remove them from the tray.