Having been asked to write a few words on growing seedlings, I say to myself, where on earth do I start. Seed collecting time will be best so here goes. After collecting the green seed on a stem, the stems are then placed in a vase with a little water until such times as they completely lose their green appearance, and the bracts turn black and look papery. Next step is to take them carefully apart to find those elusive seeds. Some heads will provide you with several seeds, others will have none. Pompons and giants are notonous for this, although on a rare occasion I had a giant which contained between ten and twenty seeds. As you find the seed, look carefully to see if it is a fat one. If you are not sure, carefully squeeze it between finger and thumb, to make certain it has some substance. Discard any that are flat and papery.
Having obtained your seed, the question is how to store them? Some people advocate placing them in a closed container until the spring. Personally I put them in sealed brown envelopes with the name of the variety which provided the seed wiitten on the outside. The variety is now known as the mother. These I then keep in a drawer in the sideboard, where they stay cool and dry until I am ready to sow them, which is usually the first week in March.
For sowing seed, I use one of the proprietary peat composts, in my case Em which I get from my local supplier. There are those who are anti peat and insist on using coir. My experience with coir, the first season I tried was an absolute disaster as I lost the lot. The second year, being a little wiser I sowed some in coir, the remainder in my usual Erin. The coir once again was nearly a complete loss, only a few seeds survived, now I only use a peat based compost.
Sowing is standard, compost is put in small 6 X 4 inch trays and very lightly pressed down, the trays are then placed in an old photographic tray in which there is clean water, with just a touch of permanganate of potash, enough to make the water a pale pink. When the compost is uniformly moist, the seed, is carefully sown, one variety in each tray. Try to space out the seed, then sift a covering of the drier compost on top, just enough to cover the seed and exclude light The trays are then placed on an open propagating bench which has a temperature set between 65 to 70, a piece of glass is then placed on top of each tray. When this is done, place your hands together, palms touching, and say your little prayer, I am sure this helps, except with coir compost.
Germination is quite erratic, first ones usually show from ten to fourteen days, the last one anything from six to eight weeks. Germination varies from nil to about 40%, although this year, I had only one pom seed, and that germinated so I could say I had 100%, but that wouldn’t be fair. As the seedlings grow large enough to handle, each is carefully teased out and replanted into 24 section propapaks, they are then carefully watered and placed in a shaded part of the greenhouse for a few days until they recover from the transplant, then they are placed in full light.
The usual greenhouse hygiene is maintained, check for any greenfly or red spider. I find a good magnifying glass is essential to check for red spider, if any of these pests appear you must deal with them immediately in the way you find best. As planting time approaches the seedlings will have been repotted into 3 inch pots, all are hardened off, ready to be planted out.
Planting time for me starts the second week in May. This I know is weeks ahead of most of you, weather is so much milder here in Cornwall. Having rotovated the bed, incorporated any farmyard manure I have been able to obtain, all I do now is to lay my support wire down. Support wire is 40 inches wide with five 8 inch spacings (chrysanth wire). Seedlings are then planted in each square, as the plants grow, so the wire is raised to support them.
I stop each plant in mid June, then give a light sprinkling of Growmore fertiliser 7N: 7P: 7K, this is the only extra feed they get.
Having watched the first flower fully develop, you then either pull it up for compost, or eagerly wait for the second bloom. If it still shows promise, label it right away, because you might not get another flower and it could get overlooked. I try, weather permitting to take a photograph of each seedling I keep. This is purely as a reminder, my memory is not as good as it once was. Doubles, singles in all shapes and sizes, this is what you can expect from a seed bed. The great joy of raising seedlings is every one is a surprise. The question you ask yourself of each one is. Is it good? Has it got the required form? Will it compete with the best at the moment? If the answer to each of these is yes, you have a potential winner. All the above are basic tasks that need to be done.
Now we go back to find out why we collected seed from particular parents. A raiser should have a goal in mind when s/he starts with seedlings. I think most of us started by collecting seed heads randomly, hoping for the best, this method, may on the odd occasion produce a winner. It is much more productive to decide what end result you are seeking, either small decorative, medium semi-cactus or one of the other classifications. I understand some raisers cross pollinate their chosen varieties with a camel hair brush, then carefully protect the seed head from further pollination. By this method you should know both parents. However I am doubtful that this can be a sure method of having a pure cross. It only needs one thrip, an aphid or one rogue pollen grain to destroy all ones calculations. I prefer to let mother nature do the crossing with a little chosen help from myself.
A couple of seasons ago Elma Elizabeth arrived from America, it was hoped this would be classified as a medium decorative, but not so. With this in mind, I have tried to get a medium decorative of the same form. To do this, I planted in a block 3 X Elma E - 3 X Ruby Wedding, 3 X Ruby Wedding - 3 X Elma E, in all twelve Elma E and twelve Ruby Wedding. Doing it this way, one would expect the majority of crosses would be between Elma E and Ruby Wedding and vice-versa Ruby Wedding and Elma E with some variable crosses from other sources. The resulting seed count was five Elma E seed and two hundred plus Ruby Wedding seed. The Elma E seed produced none that were worth keeping, this was a disappointment as I had hoped Elma E would be a good parent. Ruby Wedding seed produced several which show promise, from miniatures to smalls and mediums, including one which is a little lighter than Elma E, the same form but doser petalled and a medium.
Seedlings are notorious for changing in their second year, and sometimes in their third year. I shall have to wait and hope to see if there will be a medium of Elma E quality. As you have probably worked out, I plant in blocks those I wish to cross, this method seems to give me a reasonable proportion of doubles. During the growing season it is imperative you label those you wish to keep, in my case the name of the mother is on the label, this allows me to record successes and failures from different mothers. Some mothers that you think will make a good parent turn out to be very disappointing. One particular popular giant I tried for three seasons and got nothing more than low grade miniatures, which, makes me think there is a recessive strain and a dominant strain in the dahlia.
When the frost hits me in the autumn, the tops are cut off, tubers carefully lifted, washed, and placed upside down on slatted greenhouse staging to dry. As spring approaches a decision has to be made, do I replant the tuber or take some cuttings? Ref ening back to my growing season records and photographs, I had already marked the most promising. These are then propagated taking anything up to ten cuttings from a tuber. The second team are planted as a single of split tuber. All these are then grown to give their full potential, usually the second year will show you those that are good, also the has beens. There are nearly always one or two that take another season to reach their peak.
Size in the second year dramatically changes in most seedlings, going from miniature to small and even larger, this applies across all sizes, a giant seedling can only grow bigger. The odd seedling however stays the size you first saw it in the seed bed.
Having got your dream flower grow it to exhibition standard,
show it to some of the top exhibitors in your area and note their
reaction, this will tell you if you have a good one or not. Raisers
always tend to see swans, when you do get one it is a great thrill,
so keep trying.