Multiplying plants is free, it allows to save money, of course. Concerning the bulbs, these make small ones all alone, they are said to be self-propagating, and their offspring that we call rather rejections, bulbils, cormettes or side bulbs, are faithful to the mother plant. Division, which consists in separating these small bulbs so that they become new autonomous plants, is the best known and simplest method of bulb multiplication. Another easy way to multiply bulbs is by chipping. What is it?
What are the scaly bulbs?
As its name indicates, the scaling of bulbs to multiply them can only concern scaly bulbs, since the term derives from them.
Bulbs are diverse, and behind this term which has become generic in the common language of the gardener, there are real bulbs (lily, tulip…), corms (gladiolus, ixia…), rhizomes (iris…) and tubers (dahlia…). They are all geophytic plants, which means that they store their food and nutrients reserves in this underground organ during dormancy. Thus, they will be able to use these resources when they will be in period of growth and bloom.
Scaly bulbs are part of the true bulbs. Unlike tulip bulbs, for example, which are tunnelled, these have looser layers that resemble scales because they overlap each other. Scaly bulbs include lilies (Lilium), some fritillaries (Fritillaria), narcissus (Narcissus), hyacinths (Hyacinthus orientalis), wintergreen (Leucojum spp.), Alliums, etc.
When to propagate bulbs by scaling?
The scaling of the bulbs is done at the end of the bloom, when the leaves of the plant are desiccated, browned, that is to say, generally at the end of the summer or at the beginning of the autumn.
The division of a scale by cutting, alternative to the scaling, is practiced during the period of dormancy.
How to scale?
When the aerial parts are dead, dig up the scaled bulb and clean it carefully. Detach the scales that have developed around it, trying to separate them as close as possible to the base of the bulb. The latter, once “cleared” should be immediately replanted in its original place.
Take a plastic bag and put in a mixture of soil/compost + gravel/vermiculite which will maintain a certain humidity. Arrange the scales, trying not to touch each other. Sprinkle a pinch of sulphur for its fungicidal properties, and close the bag without evacuating the air.
Keep the bag in a warm, dry and dark place, monitoring regularly (every week or two) that the scales do not deteriorate due to mold or other fungal diseases. If this is the case and the signs are minor, wash the scales concerned before replacing them, and monitor their evolution. The substrate should retain some moisture.
Depending on heat and humidity conditions, it will take 5-8 weeks to start seeing small bulbils develop on the scales. When they are ½cm tall, you can plant each scale in a pot filled with non-draining compost, placing the bulbils just below the surface of the soil. Water and monitor their progress, in a cool place.
They will be placed in the fall but you will often have to wait up to 5 years before seeing the first flowers.
How to divide a scale by cutting
This alternative is practiced from a dormant bulb chosen for being particularly healthy. Clean the bulb and dry it then remove its roots and its old envelope, before cutting the point with a well sharpened and disinfected knife. Put the “blunt” tip on the table, and from its other side, initially the base of the bulb, cut it into 8 pieces.
Then, proceed as the chipping explained above, making sure to place the bulb quarters, with their base at the bottom. It may take a little longer to see bulblets develop (10 to 12 weeks).
Each type of bulb can multiply, you just need to know how and the book Flowering Bulbs*, by Stéphanie Mahon, journalist and author specialized in gardening, will help you enter the world of bulbs that offer flowers to the garden in all seasons, with an unsuspected diversity of shapes, colors and textures. Their ease of care is a plus, so don’t limit yourself to tulips and daffodils, discover a seasonal repertoire of more than 65 varieties suitable for all creative ideas!