Can I use seed that I didn't need in 2010? That question is often asked and the answer is always the same and it starts with the words 'it all depends'. Most vegetable seeds will keep for a few years with parsnip being the dodgy one. Herb seeds are short lived and quite a few flower seeds remain viable for just a year or maybe two. You will readily find the appropriate seed longevity charts on the Internet.
The second point to consider relates to storage. Most seeds nowadays are packaged in hermetically sealed foil sachets. After sowing, the remaining seeds can be returned to the foil envelope. Folding over the open end a couple of times should achieve a decent seal. If these packs are stored in a cool place where the temperature is likely to be constant, they will remain viable for quite some time. Finally as time goes by the viability of the seeds will start to diminish therefore you must be prepared to sow a little more thickly than is recommended, to finish up with your requisite number of plants.
From time to time Garden - Which? has published results of germination tests carried out on new seed which have shown pretty awful results. The attendant publicity would be sufficient penalty for the businesses concerned! The reason I mention this relates to the seed count in each packet and what you have to pay. Spend a little time studying the information provided, particularly the seed count.
That brings me neatly to the question of whether or not to use F1 hybrids. As you will be aware these particular cultivars are given this appellation because they are the First filial generation of a cross between two pure, self-breeding lines. The resultant seeds are expensive because the plant breeder has to maintain the male and female lines pure and separate to achieve the desired effect. What effect is that? There are several, firstly there is what is known as hybrid vigour, which is self-explanatory. With that come a number of attributes - stunning flower colours, enhanced perfume, resistance to bad weather conditions, uniformity of form, disease resistance, heavier cropping. For amateur gardeners, I suggest the F1 flowers are definitely worth growing but when it comes to vegetables, there is one snag: that uniformity which is so effective in producing a floral display is not so welcome when you plant 24 F1cauliflowers and there are 24 heads ready to be harvested on the same day! I exaggerate slightly but I tell you they can be pretty close. That said, the F1 hybrid Brussels sprouts can be absolutely marvellous, so long as you pick little and often. Favourite amongst the early introductions was Peer Gynt which I have picked from November through to March. It has undoubtedly been superseded by others as good as or even better.
Earlier, I mentioned disease resistance as one of the benefits of using F1 hybrids, staying with brassicas, there is now a range of clubroot resistant varieties. If your ground is infested look for cabbage Kilaxy or Kilaton; cauliflower Clapton; and for sprouts Crispus. All are substantially resistant to the disease.
What about collecting and storing seeds from plants in your own garden? Some things with large seeds like broad beans for example; you simply leave the pods on the plant for as long as possible, pick off and separate the beans and allow to dry. The simplest way to harvest many small seeds is to cut the flower stem as in dead-heading and drop the lot into a bag. By so doing, you are less likely to loose the seeds that have already ripened. For convenience, the first inclination is to use a polybag and I have no problem with that so long as you do not store the seeds in such a container. Take the harvested stems with seed heads facing downwards in the polybags to the garage or shed and hang them up to allow the ripening process to continue. Don't seal the neck of the bag tightly. Remember to LABEL the contents.
With the passage of time, the ripened seeds will tend to drop from the heads into the bottom of the bags, some may need a bit of encouragement by shaking or gentle rubbing. Traditionally, we would then transfer the ripe seeds to a brown paper bag or envelope (with label). Several may then be stored in an airtight jar until spring.
Earlier I mentioned F1 hybrid seeds, home saved seeds are said to be 'open-pollinated', in other words there has been no control of where the pollen has come from! As a result, the new plants are unlikely to be true to type. They are likely to be a mixture with good, bad and a whole raft of stages in between. That, for some people, is the excitement, indeed that is how many new kinds are discovered and developed.
Jim McColl presents BBC Scotland's the Beechgrove Garden.