Gadenin日本語Get the appWhen the leaves are worth picking
The best leaves come from soft young growth in spring and from the fresh regrowth that follows a hard cut in summer. Old leaves on tall stems in high summer are tough, and the aroma turns coarser and more sharply fishy as the plant approaches flowering.
The scent is strongest in the leaf just before the white bracts open, which is why most people time their main cut for the point when buds are visible but not yet showing white. After flowering the plant puts energy into seed and stems, and leaf quality falls off noticeably until you cut it back.
| Stage | Leaf quality | What to do |
|---|---|---|
| First shoots, early spring | Tender, mildest scent | Pick lightly, leave most growth to build the clump |
| Full growth, buds forming | Best aroma and texture | Take the main cut now, up to two thirds of the clump |
| In flower | Tougher, coarser scent | Cut back hard and wait for regrowth |
| Regrowth after cutting | Soft and good again | Second cut three to four weeks later |
| Late autumn, dying back | Poor, yellowing | Clear the top growth and take nothing for use |
How to cut
Cut whole stems with scissors or shears rather than pulling individual leaves. Pulling tears the stem, loosens the rhizome and leaves ragged wounds that rot in wet weather, and it is far slower for the same amount of material.
- Cut in the morning Cut before the day warms, when the stems are turgid and the leaves have not started to wilt. Cut material goes limp within an hour in warm sun.
- Cut above a pair of leaves Leave about three inches (8 cm) of stem standing with at least one node on it. New shoots come from that node and from the rhizome, and regrowth is dense within three weeks.
- Take no more than two thirds at once Cutting the whole clump to the ground is survivable but sets it back a month. Leaving a third standing keeps it growing and gives you a second cut in the same season.
- Wear gloves and expect the smell The oil transfers to skin, gloves and blades and stays there. Wash tools straight away, and do not do a big cut just before people arrive to sit in the garden.
- Bag the trimmings as you cut Put every cut stem straight into a bucket or bag rather than dropping it on the soil. Stems left lying on damp ground root at the nodes within two weeks.
Do not compost fresh fish mint stems or rhizomes in an ordinary cool garden heap. They survive and root in it. Dry them to a crisp on a hard surface first, or put them in household waste.
Handling what you pick
Fresh leaves keep about three days in a sealed box in the fridge, wrapped in a damp cloth. Beyond that they blacken at the edges and the smell turns rank rather than fresh.
Drying changes the aroma completely. Dried leaf loses almost all of the fishy note and becomes mild and hay-like, which is why some people who dislike the fresh plant find the dried leaf perfectly pleasant. Hang whole stems in small bundles in a dry, airy, shaded place, or spread them on a rack; they take about a week to become brittle. Strip the leaves off then and store them in a sealed jar away from light.
Do not dry it in a closed room in the house on a hot day. The smell is strong while the material is still damp and it lingers in soft furnishings.
Roots and rhizomes
The white rhizomes are also used, and lifting them is the one harvest that reduces the plant rather than encouraging it. Do it in autumn once the top growth has died back, when the rhizomes are easy to see against dark soil.
Work through the container or the enclosed bed systematically with a hand fork, sifting the compost and lifting every white piece you find. The rhizomes are brittle and snap under any real pull, so follow each one along its length with your fingers and ease it out whole rather than tugging. Anything you snap and leave behind will regrow, so this is worth doing slowly.
Never tip soil or compost containing fish mint rhizome onto a border, a spare corner or a green waste pile. It establishes from a fragment less than an inch long.
What to record for next year
This is a plant whose timing shifts a lot with how wet and how shaded your position is, and two seasons of notes let you cut at the right moment rather than guessing.
- The date the first shoots broke ground Note it each spring against the position. Comparing years tells you how early your particular corner warms up and when to start looking for buds.
- The date buds first showed The main cut goes just before this. Once you know the interval between first shoots and first buds in your garden, you can plan the cut a fortnight ahead.
- How much you cut, and how long regrowth took Write down the fraction cut and the number of days to usable regrowth. That tells you whether a second cut in the same season is realistic where you are.
- Where every stray shoot appeared Mark the position of anything that came up outside the container. A pattern across two years shows you the escape route, which is nearly always a drainage hole or an overhanging stem.