1/ Alan Romans: www.alanromans.com and 01337 831060. The potato site … although it also has other veg and flower seeds, and potato microplants when your learning curve is not so sharp.

2/ Crocus: www.crocus.co.uk and 0870 7871414. Excellent for tools, water butts, and loads of information and advice on pests and methods (non-chemical and chemical) of getting rid of them.

3/ D.T. Brown: www.dtbrownseeds.co.uk and 0845 1662275. Fruit trees, rhubarb, vines and figs, asparagus crowns, and a nice selection of tomato seeds for growing on the patio.

4/ Edwin Tucker & Sons Ltd: www.edwintucker.com and 01364 652233. Excellent on potatoes (and good if you phone for advice). Also GM-free and organic seeds (including green manures and, as a real bonus, lawn seeds for all sorts of difficult areas). Pictures of plants only on the covers but it tells you everything you need to know.

5/ Harrod Horticultural: www.harrodhorticultural.com and 0845 4025300. Greenhouse and horticultural equipment, organic fertilisers and pest control.

6/ Jekka’s Herb Farm: www.jekkasherbfarm.com and 01454 418878. Sells plants (organic, peat-free) and seeds. Jekka’s Choice Salad Herb Mix is a favourite.

7/ Kings Seeds: www.kingsseeds.com and 01376 570000. A good catalogue. Good, too, for sundries (soil testing kits, cloches, netting for plant protection, etc). Its sister sites, www.kingsplants.co.uk and www.suffolkherbs.com, sell herbs and veg ready to plant out.

8/ Marshalls: www.marshalls-seeds.co.uk and 01480 443390. One of the heavyweights. Potatoes, onions, fruit, herbs … plus vegetable starter plants.

9/ Medwyn’s of Anglesey: www.medwynsofanglesey.co.uk and 01248 714851. You may think that this is only for the vegetable show enthusiast but it also has interesting veg that children may like to try – a sweetcorn called Lark, for one.

10/ Mr Fothergill’s: www.fothergills.co.uk and 0845 1662511. Excellent website. Loads of information and pages easy to print out so that you can keep a record of what you’ve planted and how to grow them.

11/ Organic Gardening: www.OrganicCatalogue.com and 0845 1301304. A good all-round seed catalogue … vegetables, flower and wildlife meadow seeds, plus excellent sundries (“homes” for wildlife, worm composting bins, fertilisers, etc).

12/ Pennard Plants: www.pennardplants.com and 01749 860039. Heirloom seeds, some varieties are more than 50 years old. If you’re keen on growing runner beans for the flowers, try the Mixed Colours For Summer with their pink, white and scarlet flowers.

13/ Plants of Distinction: www.plantsofdistinction.co.uk and 01449 721720. A family-run business. Surely no one will be able to resist trying the Rainbow Mixed carrots on the 2007 catalogue front cover?

14/ Samuel Dobies & Son: www.dobies.co.uk and 0870 1123625. Long-established firm. Fruit and vegetable seeds, mushroom kits and young plants.

15/ Seeds of Italy: www.seedsofitaly.com and 020-8427 5020. Italy comes to Harrow … all those lovely foreign seeds without everyone having to travel to buy them.

16/ Simpson’s Seeds: www.simpsonsseeds.co.uk and 01985 845004. Another text-only catalogue. Interesting varieties.

17/ Thompson & Morgan: www.thompson-morgan.com and 01473 695225. Veg and flower catalogue … the lettuce front cover is worth copying in your own garden.

18/ Two Wests & Elliott: www.twowests.co.uk and 0870 4448277. Greenhouse and gardening equipment.

19/ Unwins: www.unwinsdirect.co.uk and 01480 443395. Good vegetable starter plants … for all those vegetables you’ve tried to start off and have never performed for you (celeriac, to name one).

20/ W. Robinson & Son: www.mammothonion.co.uk and 01524 791210 (and www.exhibition-seed.info for help with common problems). Don’t let the online name put you off … their Show Perfection pea is yummy, yummy, yummy and the Purple Podded pea is simply beautiful.

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