I put about twenty stems of parsley on the compost heap one evening in August and stood there feeling genuinely annoyed with myself. I had grown it, watered it through a dry spell, picked it on Sunday with good intentions, put it in the fridge, and forgotten it until it was slime in a bag. That was the season I started taking the glut seriously.
Herbs do not arrive at a sensible rate. They sit there doing very little in spring, then one warm fortnight in July hands you more basil than you could eat in a month. Fresh is best and fresh is also finite, so the question is what to do on the day you pick, not the day it wilts.
Freeze first, dry second
My default now is the freezer, because for the soft herbs it keeps far more of the flavour than drying does. Basil, parsley, coriander, chives and mint all freeze better than they dry, in my experience. Dried basil in particular tastes like a different, sadder plant.
The simplest version needs no equipment. I chop the herb, spread it thin on a tray, freeze it loose, then tip it into a bag or a box. It clumps a bit anyway, but I can break a lump off with a spoon. It comes out limp and dark, so it is no use as a garnish, but stirred into a sauce or a soup or a pot of beans it does its job.
Drying I now keep for the woody ones. Thyme, rosemary, sage and oregano dry well because the flavour holds up. I tie a bunch, hang it somewhere dry and out of direct sun, wait until the leaves crumble between my fingers, then strip them into a jar. No oven, no gadget, no fixed timetable. It takes as long as it takes, usually a week or two depending on the weather.
The oil cube, which is the one I actually use
The method that changed my summer is chopping herbs, packing them into an ice cube tray, and topping each one up with olive oil before freezing. The oil coats the leaf and it keeps colour and flavour far better than freezing dry does.
Then, in November, a cube goes straight into a hot pan at the start of something. It melts into a slick of green oil and the kitchen smells like July for a second. This works particularly well for basil and for a rough mix of parsley with garlic.
Two practical notes. Use a tray you do not mind smelling of garlic forever, because it will. And pop the cubes out into a bag once frozen, because a tray of herb cubes will otherwise occupy your freezer for the entire winter and someone in the house will complain.
Dishes that eat a fistful, not a pinch
Before preserving anything I try to just use more. Most recipes call for a garnish quantity of herbs and that is why gluts happen. There is a category of dish where the herb is the main ingredient, and those are the ones that actually clear a plant.
A big grain salad is the best one I know. Cooled bulgur or couscous, an unreasonable amount of chopped parsley, a serious handful of mint, spring onion, lemon and oil. I mean whole bunches, not a sprinkle. It absorbs herbs at a rate nothing else in my kitchen matches.
Pesto is the obvious answer for basil and it works, though I have stopped restricting myself to basil for it. A rough blend of parsley with garlic, nuts, cheese and oil is not traditional and it is very good on pasta and better on a baked potato. Salsa verde, which is basically herbs, capers, mustard, vinegar and oil chopped together, uses more herbs than any sauce should and goes with roast anything.
Salt and vinegar as parking spots
Two lower effort options I return to. Herb salt is chopped herb pounded or blitzed with coarse salt and then dried out on a tray somewhere warm. It goes on eggs, potatoes and roast vegetables and it lives in a jar for months. Rosemary and thyme work best. It is a way of storing flavour without pretending you have preserved the herb itself.
The other is putting woody herbs in vinegar. A few thyme or rosemary sprigs in a bottle of white wine vinegar for a couple of weeks gives you something useful for dressings, and the bottle looks good enough that I have given several away as presents. I keep it in the fridge once the herbs are in, and I fish them out once it tastes strong enough.
Give it away, and cut anyway
The unglamorous solution is handing bunches to neighbours, and it works better than any preserving method because it costs zero minutes. I keep a few paper bags by the back door in summer for exactly this. Nobody has ever refused a bunch of basil.
The thing I had to unlearn is that leaving herbs on the plant is not saving them. A basil plant left uncut goes to flower and the leaves change. Mint left uncut gets leggy. The glut is not a problem caused by cutting too much. It is what happens when a plant is doing well, and the choice is to use it, save it, give it away, or watch the quality drop.
So now I cut on a schedule regardless of appetite, and the plants stay productive, and the freezer fills up with green cubes that make February dinners noticeably better.