Unless you're one of those gardeners who operates a scorched earth policy, someone who is trigger-happy with the weed killer, be consoled by the philosophical observation that a weed is just a plant in the wrong place.

As a veteran in the war against ground elder - as pointless and unwinnable as that in Afghanistan - I have learned to live alongside it. Peace talks made progress when I learned that it's edible. Now when I see those resilient jaggy shoots standing to attention, where everything else has been attacked by slugs, I think: "Oh great, salad." The vigour of this tenacious plant knocks spots off those gas-flushed packs of flaccid supermarket salad leaves, and even if that's all you've got, a few leaves of elder inject the vitality of the allotment into your salad. The flavour is not bad either, mildly acidic and clean.

The gastronomic potential of ground elder, and a whole squad of underutilised edible plants, comes as no news to the people who run the Secret Herb Garden outside Edinburgh. Some people will remember when this concern was called Damhead, growing a good little selection of organic vegetables and herbs and supplying these, and other organic dried goods, to shops and restaurants. When it sadly closed, it left a gap, which has now been filled in the most creative way. The new owners, who have some connection with Jekka McVicar, Britain's doyenne of herb cultivation, have renewed and re-opened the place. They cultivate their own seeds; you can buy them there.

If you're looking for food to eat, as opposed to food to grow, the Secret Herb Garden is a work in progress. An attractive vintage glasshouse is at the heart of the operation, filled with edible greens of all sorts: rampant parsley, lavender, thyme, rosemary, fennel. In amongst the greenery is a random collection of well-worn garden furniture. On a good day, you can eat "outside" in the glasshouse. These old glasshouses were designed to keep in the heat, and this one is remarkably cosy, even when it's quite parky outdoors.

In a separate building, there's a cafe cum shop, serving a relatively limited menu, for the time being, of fresh, but cold, food. A larger kitchen, allowing hot cooking, is phase two. But already, the hallmark of the small selection is herbs with everything. There are quiches, but not as we know them: more imaginative. I'd never have thought of putting celeriac and parsnip in a vegetable tart, but combined with cheddar, and fistfuls of hyssop, it worked surprisingly well. Ditto apple, carrot, goat cheese and tarragon - that combination would never have occurred to me - but was another hit, and picking up the flavour of the just-picked tarragon made me realise how faded so many of those supposedly fresh packs of herbs are in the shops. Spring onion, bacon and potato made another first for me, but I was pleased to make its acquaintance. Crumbly pastry and melting meaty, oniony, potato bound lightly by eggs and milk? Nice one.

There's some wise sourcing too, from bakery Andante in Morningside: twists of butter puff pastry with goat cheese and pulpy tomato centres. All would benefit from being heated, but they were so recently made, and happily not refrigerated, that it didn't terribly matter.

I might try flogging them some of my ground elder for the salad - it would fit into the biodiverse mix, which, that day, was ruby chard, spinach thinnings, nastursium, chickweed, marigold petals, and white sorrel, well coated in a mustardy mayonnaise. Sometimes sticky willy (aka cleavers, goosefoot) goes into the mix. Quiche and salad (admittedly a small portion), only costs £4.50.

If you fancy tea and cake before you have a look at the beehives, seeds and plants, or the antique furniture, there's tea from the admirable Pekoe, a nice-looking line of cakes: brownie, carrot cake, lemon poppy seed and an interesting apple, sage and cinnamon number.

The Secret Herb Garden is not only wildlife-friendly, but child-friendly. In the glasshouse, kids are actively encouraged to play. In fact, it's a fun place, fresh and original.