Feeling a bit short of cash? Why not turn your garden into a gold mine by selling plants that are surplus to requirements? It can be fun, even addictive, and – who knows? – it might even lead to greater things.

Take Janet Brown. Twenty-five years ago, she thought that the rockery in her garden in the Northumberland village of Etal needed thinning out. But rather than burn or compost the plants she had pulled out, she started selling them to the tourists who pass her home on their way to a nearby ruined castle.

Today, Jan’s Plants is open from 9am to 5pm, seven days a week. Brown has a 40ft plastic tunnel, two large glasshouses and plenty of frames. About 90% of the plants she sells, she grows herself – but business is going so well that she has had to start buying some in.

“It pays for a really decent holiday every year or two, and it’s such a nice, relaxing thing to do,” says Brown, 62. “The visitors are such great fun, too. I’ve made friends of many of them, from all walks of life, and, as a lot of them holiday in the nearby Ford and Etal estate cottages, we see them year after year.” She pays business rates on the part of the garden she uses for her enterprise and advertises on the estate’s website.

Given energy and determination – and, of course green fingers – it’s easy enough to follow in Brown’s footsteps. The simplest way to start is to do as she did: set up a stall at your gate and sell your extra courgette seedlings for 50p, or theAnemonexhybridathat was invading the path for £2.50. (You should check first with the local authorities that you are allowed to do so.)

If you have more surplus plants to shift, or higher ambitions, you can reach more potential customers by selling through a nearby garden that is open for the National Gardens Scheme or another charity. They should be keen, provided you offer a percentage of your takings for the relevant good cause. Remember, though, to mark clearly that you are the one selling the plants, otherwise you will be legally obliged to hand over all the money raised to the charity.

Plant fairs and farmers’ markets are also good outlets – stalls tend to cost £25-£40. If you do not have enough stock for a whole day’s sales, team up with some fellow growers.

Now that you’re ready to sell, what plants should you go for? The most profitable are perennial flowers, herbs or shrubs: common varieties in 6in pots should fetch about £3.50, fancier ones £4-£5 and rarities £6 and upwards. For larger specimens, such as buxus in a 1ft-wide pot, clipped into a ball, you might get as much as £40. Better still, specialise in a plant group. Good ones with high margins include ferns (from £4), violas (£3.50) and hardy orchids (£5-£30). Put a 25% premium on anything that’s in flower and looking great.

You should bear in mind that some plants are the subject of breeders’ rights.

You can propagate them for your own use, but selling them on without a licence is illegal – even if, in practice, hard to police. If you think your plant may be subject to restrictions, check on the database of the Community Plant Variety Office (www.cpvo.europa.eu).

Want to follow a more high-tech route? Then try selling through eBay. You don’t need to be a computer whizz; simply pop in the details of your plants. The company charges a small listings fee for each item and takes 10% of the final sale price.

If you are selling through the site, it is probably simplest to start just with the UK before you are tempted to go global. To work out your postage and packing costs, make up a trial parcel, then check how much postage will be on postagerates.org.uk.

Tough roots, well wrapped, can be posted in a padded envelope. Juicy-rooted plants and all bulbs need a box to protect them. Rooted shrub cuttings should have their rootballs wrapped in clingfilm and be posted in boxes. Stabilise the plant in its box with crumpled newspaper. Fifty large padded envelopes cost about £25. Scrounge some boxes from local shops; big ones are easily cut down.

How much you charge for the plants themselves depends on their rarity and desirability. Recent sales I have seen include £6 for the gorgeous iris ‘Cliffs of Dover’ and up to £75 for one of the new Japanese double forms of Hepatica nobilis.

If you want to get really serious, a polytunnel is a big help, though you will need to hand-water its contents, which is a time-consuming business. A manageable 8ft by 15ft tunnel costs about £300.

A proper nursery, with about an acre of production and sales space, and four tunnels, could turn over £100,000 a year through mail order, fairs and gate sales, but don’t forget you will have to pay the staff out of that. You are unlikely to get rich – and will have to work like a Trojan – but you’ll have a wonderful time in the process.

Jan’s Plants; ford-and-etal.co.uk. For details of farmers’ markets across the UK, visit farmersmarkets.net; for London, go to lfm.org.uk; for Scotland, see scottishfarmersmarkets.co.uk. Buy and sell at ebay.co.uk and www.theplantexchange.co.uk

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