For a start, you need some small scissors to nip off the seed heads. Of course, you can use your fingers, but some seedpods are sticky and you end up with bits sticking to you (geraniums can be very messy), or your fingernails start to shred.

You need a supply of paper bags or envelopes to put the seed heads in as soon as they're cut. You need to label the envelopes immediately. It's amazing how quickly you forget if that envelope contains ordinary blue Geranium pratense or the pale blue one. For carrying these envelopes from plant to plant, a small box is useful. Some of the seeds won't be ripe. Sometimes they won't even be mature enough to ripen and you'll have to add them to the compost heap. But the majority will ripen properly if you put them somewhere dry. At this stage, they really need to have enough room for the air to circulate, so ideally they should be put in rather bigger paper containers than the original collection envelopes. There is a difficulty here, in that the paper bags such as my grandmother always had in her kitchen drawer are becoming harder to find. Plastic bags won't do for drying seeds. The problem can be solved using old telephone directories - stick two pages together on three sides, or use sheets of newspaper or the envelopes provided with junk mail.

Always harvest your seeds when it's dry. Around mid-day or early afternoon on a sunny day is ideal, but try not to collect them when they're damp. If you can't avoid it, lay them out separately on newspaper to dry out before putting them together in paper bags.

Once your seeds are dry you need to encourage the laggards to come out of their shells, so to speak. A cocktail stick comes in handy. It's particularly useful for the last few seeds in an Aquilegia pod, or (another sticky one) Polemoniums. The embroidery scissors come in useful again here, as some seedpods don't like to burst without encouragement, so cut the pods of Sisyrinchiums and Penstemons in half before giving their bag a good shaking. Sometimes, it's helpful to crush hard seedpods to break them open. A rolling pin comes in handy here.

To collect the seeds themselves, you need several sheets of paper. With most seeds you collect a lot of rubbish in the way of bits of seedpod, mud, small spiders, tiny orange grubs. A couple of tea strainers are useful - one with quite big holes, for removing the unwanted small bits from fairly large seed. The other with a smaller mesh to let dust through, or lets the small seeds through and keeps the bigger bits of rubbish out. If the seeds are largish, a pair of tweezers can be used for picking them up. If the seeds are small, you can separate them from some of their chaff by holding the paper at an angle and letting the seed roll down - the other stuff generally stays put. A combination of these methods usually results in more or less 100% seed only.

After separating the seed, you need to make absolutely sure it's dry before you store it. Damp seed will rot. Leave the seed for a couple of days in a dry environment, then

pack it in paper envelopes. Do remember to label the envelopes clearly. Keep the seeds cool, dark and dry.

When do I collect the seeds? ~ You cannot collect seeds from dead flowers. The seeds need to mature and then they need to ripen. Think of an apple - you know you can't eat the little green apples that you see when the flowers have died. It's the same with other seed containers - they need to grow bigger and mature before they are any good. Seed production is a three-stage process: first, the seeds have to be fertilised, then they have to mature, then they have to ripen. If they haven’t been fertilised, they won't mature. If they haven't been fertilised and grown to maturity, they won't ripen. If they haven't been fertilised, matured, and ripened, they won't be viable. Sometimes, it takes weeks or even months from the time the flower dies to when the seeds are ready.

How do I tell if they're ripe? ~ When the seeds are ripe, nature will disperse them. If you want to collect them yourself, you need to wait until just before they would be dispersed naturally, because you know that they will be ripe then. The seed pod will become dry and will usually change colour, probably from green to brown or white, and the seeds inside will change from green or white to brown or black. Think of the apple again - the seeds inside an unripe apple are white. When the apple is ripe, it changes colour and the seeds inside become brown.

How do I know if seeds are viable? ~ Viable seeds are healthy seeds. Often, they look healthy - they're shiny, fat, heavy and tough (all relative to the weight and size of a seed). Sometimes, they aren't all those things, but a good seed – even a flat one like a lily - will still have a bit of 'body' where the embryo is, or be too strong to squash or cut with a finger nail.

What's a Float Test? ~ There's a theory that seeds float if they're no good, and good seeds sink. That might apply to the seeds of a particular type, but it isn't a good rule to follow. Seeds will float if they're lighter than water and sink if they're heavier than water. Some seeds will germinate while floating (apparently, you can germinate some lily seeds this way), and some seeds will float until you make a hole in their seed coat, and then they'll sink.

What are Open-Pollinated Seeds? ~ Left to the bees and other natural pollinators, plants produce seeds that are the result of pollination with any other compatible plants in the area. Open-pollinated seeds are what you get naturally. Seeds saved from open-pollinated plants will give you more or less the same mixture of colours, sizes or heights as the original plants.

What are Hybrids? ~ Hybrids are plants with mixed parentage. They're plants with a large number of genes for different things (colour, height, size of flowers) in them, so you get a mixture of colours, heights and flower size from their seeds. If seed growers have selected one thing, such as colour, and grown only the plants that have

flowers with that colour, and collected seeds from only that colour, and done that for several generations of plants, you'll end up with plants that have mostly that colour flowers. But they will still have a few genes for other colours, and if they are grown near other plants of the same type with other colour flowers, they will cross-fertilise and the seeds will have genes for all the colours, and will produce plants with different colours.

What are F1 Hybrids? ~ F1 Hybrids are seeds of two particular plants that growers have cross-pollinated. They are the first generation of plants produced from the cross, and can only be produced by crossing the two particular parent plants again. Seed saved from F1 plants will not produce the F1 hybrid. They are then open-pollinated.