Vegetative Propagation of Fritillaria
by Joy Bishop
The following is taken from Fritillaria Group Journal No.9 (Autumn 2001).
Seed sowing is my preferred method of increasing my fritillary collection, better even than rice which I find can take as long as seed to grow to flowering size with the added risk of introducing disease. Nevertheless I do regularly slice up a few bulbs each year as this method, when successful, will result in flowering bulbs in about three years. It is surprising that so few growers practice this procedure which is not complicated.
It was in E.B.Anderson's DWARF BULBS FOR THE ROCK GARDEN (which I acquired in the auction at the 1971 International Conference in Harrogate) that I first read of this practice although he had not tackled fritillaries. His method of slicing Galanthus and Narcissus was tried and I was delighted with the results, seldom having failures which are not the case with fritillaries, they are a little more difficult. Since then many other true bulbs have been tried, also tubers of Corydalis (Leonticoides section) and Cyclamen.
It would not have occurred to me to slice up fritillary bulbs in the same manner if I had not read a booklet published, I believe, by the Ministry of Agriculture and Fisheries, on the commercial propagation of F. imperalis and describing the cutting method. The system which I have used since has been adapted from this. It usually works for me but I do have some failures, seldom risking more than one bulb of a species per year. Naturally your trials will be with a species of which you have a surplus but when confidence is attained then the rarer the bulb the more worthwhile the venture.
The procedure is carried out when the plant is dormant. June is the best time because it allows a good three months for the bulblets to form and potting can be done with the main collection in September or October. The bulb must be healthy and flowering size. At this time the simplest and safest but modest method of increase is to pull the two scales apart, the piece with the shoot may still bloom the following spring while the other will form a new bulb to flower in one or two years depending on vigour. I usually bury the two pieces in sand in a labelled plastic cup until potting time.
Most important is cleanliness and although it is impossible to have sterile conditions in one's potting shed, it is necessary to work as aseptically as possible. The cutting surface (I use a glazed tile or a square of glass) is swabbed with spirit, and the knife blade passed through a flame or a new razor blade used, for each bulb. A strong solution of fungicide is made up; Benlate was used until it was withdrawn, since then I have used Supercarb with equal success - one sachet in 1.1 litres (2 pints) of water, following the instructions on the packet for bulbs and corms. Plastic sandwich bags, an indelible marker and a supply of vermiculite are required.
First write on the bag the name and source of the bulb and the date of cutting. Swab the tile with spirit and with the bulb standing upright slice into quarters then each quarter in half again all through the base plate. If the bulb is cut keeping the shoot intact in one of the eighths it may possibly bloom in the spring in spite of the disturbance; there is no guarantee although I have had it happen a few times. Recently, and if a bulb I wish to propagate is very rare, I have merely halved the bulb and sliced into four only the half with no shoot, preserving and growing on the other half as usual. Following cutting soak the pieces in a little of the fungicide in a labelled plastic cup for about twenty minutes then drain through a strainer and place in the appropriately labelled plastic bag with a handful of slightly damp, not wet, vermiculite. Seal the bag and place in a temperature of 15 -20 °C. (60 -70°F). The airing cupboard is often recommended but when tried I found the bag's contents dried too much and died. In my experience the temperature is not crucial. My bags are placed on a tray in the darkest part of the potting area and left to take what temperature the summer provides. When it has been colder than usual the bulblets just take longer to form.
The bags are then left undisturbed for three months when the contents can be tipped out and inspected. The pieces of bulb will have darkened and small white shoots can be seen. Pot up, still attached to the piece of old bulb, in the usual bulb compost and grow on normally, feeding occasionally. The sizes of the shoots vary, they are not as obviously bulb-like as with Galanthus but as long as there is a shoot it will grow. If they are very tiny, reseal the bag and wait two or three weeks before re-examining. If roots start to form pot up immediately. Repot each September.
This is the method that has evolved and works for me. If I were a scientist with access to sterile laboratory conditions then this might be a different story.
by Joy Bishop
The following is taken from Fritillaria Group Journal No.9 (Autumn 2001).
Seed sowing is my preferred method of increasing my fritillary collection, better even than rice which I find can take as long as seed to grow to flowering size with the added risk of introducing disease. Nevertheless I do regularly slice up a few bulbs each year as this method, when successful, will result in flowering bulbs in about three years. It is surprising that so few growers practice this procedure which is not complicated.
It was in E.B.Anderson's DWARF BULBS FOR THE ROCK GARDEN (which I acquired in the auction at the 1971 International Conference in Harrogate) that I first read of this practice although he had not tackled fritillaries. His method of slicing Galanthus and Narcissus was tried and I was delighted with the results, seldom having failures which are not the case with fritillaries, they are a little more difficult. Since then many other true bulbs have been tried, also tubers of Corydalis (Leonticoides section) and Cyclamen.
It would not have occurred to me to slice up fritillary bulbs in the same manner if I had not read a booklet published, I believe, by the Ministry of Agriculture and Fisheries, on the commercial propagation of F. imperalis and describing the cutting method. The system which I have used since has been adapted from this. It usually works for me but I do have some failures, seldom risking more than one bulb of a species per year. Naturally your trials will be with a species of which you have a surplus but when confidence is attained then the rarer the bulb the more worthwhile the venture.
The procedure is carried out when the plant is dormant. June is the best time because it allows a good three months for the bulblets to form and potting can be done with the main collection in September or October. The bulb must be healthy and flowering size. At this time the simplest and safest but modest method of increase is to pull the two scales apart, the piece with the shoot may still bloom the following spring while the other will form a new bulb to flower in one or two years depending on vigour. I usually bury the two pieces in sand in a labelled plastic cup until potting time.
Most important is cleanliness and although it is impossible to have sterile conditions in one's potting shed, it is necessary to work as aseptically as possible. The cutting surface (I use a glazed tile or a square of glass) is swabbed with spirit, and the knife blade passed through a flame or a new razor blade used, for each bulb. A strong solution of fungicide is made up; Benlate was used until it was withdrawn, since then I have used Supercarb with equal success - one sachet in 1.1 litres (2 pints) of water, following the instructions on the packet for bulbs and corms. Plastic sandwich bags, an indelible marker and a supply of vermiculite are required.
First write on the bag the name and source of the bulb and the date of cutting. Swab the tile with spirit and with the bulb standing upright slice into quarters then each quarter in half again all through the base plate. If the bulb is cut keeping the shoot intact in one of the eighths it may possibly bloom in the spring in spite of the disturbance; there is no guarantee although I have had it happen a few times. Recently, and if a bulb I wish to propagate is very rare, I have merely halved the bulb and sliced into four only the half with no shoot, preserving and growing on the other half as usual. Following cutting soak the pieces in a little of the fungicide in a labelled plastic cup for about twenty minutes then drain through a strainer and place in the appropriately labelled plastic bag with a handful of slightly damp, not wet, vermiculite. Seal the bag and place in a temperature of 15 -20 °C. (60 -70°F). The airing cupboard is often recommended but when tried I found the bag's contents dried too much and died. In my experience the temperature is not crucial. My bags are placed on a tray in the darkest part of the potting area and left to take what temperature the summer provides. When it has been colder than usual the bulblets just take longer to form.
The bags are then left undisturbed for three months when the contents can be tipped out and inspected. The pieces of bulb will have darkened and small white shoots can be seen. Pot up, still attached to the piece of old bulb, in the usual bulb compost and grow on normally, feeding occasionally. The sizes of the shoots vary, they are not as obviously bulb-like as with Galanthus but as long as there is a shoot it will grow. If they are very tiny, reseal the bag and wait two or three weeks before re-examining. If roots start to form pot up immediately. Repot each September.
This is the method that has evolved and works for me. If I were a scientist with access to sterile laboratory conditions then this might be a different story.