Outdoor Classroom: digging out large, clumping plants.

1) Huge, clumping plants which have outgrown their space can be a challenge because it is not always easy to know where to start and they have to be dug out, as opposed to cutting off woody plants. This is an unusual plant called Curculigo recurvata which has grown enormous but many home gardeners may have large clumps of flax or astelia. (The dog is Zephyr.)

2) A reasonably fit and strong person is necessary, armed with a sharp spade. Don’t try it with a blunt spade because it requires a combination of cutting and digging. Sometimes an axe is helpful to cut through big masses of crown. (The suitably strong person is our Lloyd.)

3) Sort out if you have any underground wires or pipes before you start. We didn’t this time. Fortunately the pipe supplying water to our house was alkathene so it was easy to repair.

4) Clear a space around the plant. You need room to move so lift anything precious close by. Starting from the outside perimeter of the clump, take off the sections piece by piece. Don’t try and dig the whole plant at once.

5) Taking it off in sections makes the process manageable. Because this is a relatively rare plant, we will be using some divisions elsewhere in the garden and potting some for sale.

6) We left three small clumps to grow again in the original position. If you are removing the entire plant, the critical part is to get all the foliage and the growth shoots from the base of the clump cut off and removed. It doesn’t usually matter if some of the fibrous roots remain because few plants will grow away again from severed roots. Leaves such as flax or astelia take a very long time to rot down and don’t compost well so we chew them up in the mulcher. You may need to take them for green waste recycling or put them in a discreet place to rot down over the next few years.