Gardening: seeds.

Choosing seeds for borders, containers and the veg garden is one of the most enjoyable times in the gardening year. We all have our favourite plants: mine include scented sweet peas that flower over a long period, and vegetables with some disease resistance that produce a good harvest. These will certainly fill most of the garden.

When compiling the seed order, check you really need to buy more of your favourites – you might well already have some from last year. Vegetable-seed packets carry a sow-by date as they must meet minimum germination standards. Germination rates fall with age, or if an open packet is stored badly. A few vegetables, such as parsnips, have a very short shelf life but others, such as brassicas and legumes, will be viable for longer than is suggested on the packet. When germination rates fall, I merely sow more seed than I'll finally need.

I keep on top of my sowing programme by having a large envelope for every month of the year. The varieties are written on the envelope, so when ordering fresh supplies, it's easy to check seed packets against the list and order if necessary. I simply add new varieties to the list and remove any that weren't up to the mark. I also find it's useful to prepare a database and record sowing, planting and harvesting times, with a wee comment on how the plants fared.

By the time I harvest a new crop in, say, September, I've often forgotten why I chose it way back in January. Old age, I guess. The solution is to have a column on my database to remind me why I selected a new variety. This makes it easier, when pricking out and planting, to keep it apart from the plants I know well. The calabrese variety, Fiesta F1, is a fine, traditional vegetable with a good head, but I'll be trying out Brokali Apollo F1 this year and will treat it differently to the other calabrese by cutting the head early to get lots of side-shoots.

There's always the risk that a new variety might not live up to expectations, so I limit myself to a few each year. One of these is Relic, a new loose-leafed lettuce – ideal for a sandwich. This was bred from the heirloom Deer's Tongue, it's apparently mildew-resistant and is slow to bolt during hot weather, both common problems with lettuces. Another I wouldn't be without is broad bean. Sadly, dwarf ones such as Bonny Lad are hard to track down. I've not been happy with The Sutton, so will certainly be trying out the new Robin Hood.

It's frustrating when a favourite, such as Bonny Lad, disappears from the catalogues but seedsmen are constantly developing more disease-resistant and uniform varieties. These are usually F1 hybrids, and though they solve some of our problems, there may be drawbacks. Because they were first developed for commercial growers, they will reach maturity at the same time, so may not give the long picking time we gardeners want. They may look alike, but may not be as tasty as the more traditional heirloom varieties. Old varieties, like the potato Highland Burgundy Red, often have an amazing flavour but no disease resistance. So, when choosing seeds, remember that F1s and heirlooms both have strengths and weaknesses.

If you have a yen for something unusual, the internet will come to the rescue. Suffolk Herbs – at www.suffolkherbs.com – offer an impressive selection of traditional cottage garden flowers and herbs including my favourite sweet pea, Painted Lady, with pink and white flowers and an unbeatable scent. Other plants with a difference include Ageratum Blue Ball, boasting subtle pale blue flowers, Papaver Moondance, an outstanding poppy with lemon-yellow flowers, and the dark purple-blue flowered Larkspur consolida ambigua.

For a selection of sweet peas, you needn't look further than Sarah Raven at www.sarahraven.com. She provides 45 stunningly different choices, like Lathyratus odoratus Almost Black. This sits beautifully beside the plain white Mrs Coller's. When thinking about flowers for cutting, Raven offers a wide selection, including nicotianas. One cracker is Nicotiana alata Lime Green with velvety, acid-green trumpet flowers that mix with any colour.

There's also a reasonable selection of nicotianas at Nicky's Nursery, www.nickys-nursery.co.uk. Hot Chocolate has starry ruby red to chocolate flowers and works well in borders or large containers. Salvias are another speciality. Salvia maroccana Beakbeano produces a mass of distinct arching spikes with lots of beak-like flowers, in a soft powdery lilac. I'm only giving a whiff of these sites, but I can guarantee you'll find something out of the ordinary there.