Gadenin日本語Get the appThree reasons to cut it
Cutting mint is not tidying. It is what keeps the aroma strong, keeps air moving through a dense clump so the base does not rot, and stops the plant flowering and going woody.
If you only ever do one thing to a mint plant, cut it back hard before the humid part of summer. That single cut does more for the plant's lifespan than anything else.
If you are unsure how much to take, leave about a third of the plant standing. Even cutting every leaf off is survivable, because the runners will shoot again.
When and how far
You do not have to do all four. The late spring cut is the one that matters most, and it happens to give you the largest single harvest of the year.
| When | Cut to | Purpose |
|---|---|---|
| Late spring | A third of the height | Air through the clump before humid weather |
| As buds appear | Two nodes below the flower | Stop flowering, keep the leaf quality |
| Late summer | Half the height | Bring on soft autumn growth and extend picking |
| Late autumn | To ground level | Clear dead growth so disease does not overwinter |
The late spring cut
Take the whole clump down to about a third of its height with shears, cutting above a pair of leaves wherever you can. It looks drastic and the plant is back to full size within a few weeks.
Everything you cut is usable. Whatever you cannot get through fresh can be dried, and cuttings from it root readily if you want to replace a tired plant.
When a clump suffers in summer
A dense mint clump in humid weather is the classic situation for the base to rot and for pests to build up unnoticed. Most of it is fixed by cutting and moving the pot.
| Symptom | Likely cause | What to do |
|---|---|---|
| Lower leaves blackening and dropping | Humidity and wet at the base | Cut by half for airflow and move the pot to half shade |
| Leaves going pale and stippled | Mites in dry weather | Spray water under the leaves and cut damaged stems out |
| Orange powder on leaf undersides | Rust, from crowding and damp | Collect and dispose of affected leaves and cut the clump low |
| New shoots crumpled with insects on them | Aphids | Pinch the shoot tips out and grow on the clean shoots |
Cutting too much or too late
Neither is serious. Cut too hard and the plant regrows from the runners within weeks. Cut too late, after flowering, and the leaves you have are tough, but cutting anyway brings on new soft growth.
The only genuine mistake is not cutting at all, which gives you a woody clump with small leaves and a rotting center.
Watering, feeding and position around a cut
After a hard cut the plant has far less leaf, so it needs less water for a week or two. Keep it damp rather than wet, and do not feed it heavily to make it grow back faster, because that gives you leaf with weak scent.
Do not move the plant to a much brighter position immediately after cutting. New growth scorches. Increase the light over several days if you are moving it.
Cutting differently as the plant ages
A first year plant needs little more than the flower buds removing. From the second year the clump is dense enough to need the hard spring cut, and by the third year the center is usually old and woody.
Rather than trying to rejuvenate an old clump indefinitely, plan to replace it. Deciding in advance to divide and replant every second year means you never have to agonise over throwing an old plant away, and the scent never declines.