Flower Bulbs

Infobox on Flower Bulbs
Example of Flower Bulbs
Facts
Origin	Mostly the Netherlands
Stowage factor (in m3/t)	-
Humidity / moisture	See text
Ventilation	See text
Risk factors	See text

Flower Bulbs

Description / Application / Shipment / Storage

Bulb production

In bulb cultivation, a distinction is made between spring-flowering and summer-flowering plants. Growers plant the small bulbs (the planting stock) from this first group that includes tulips, narcissi, hyacinths and crocus in the autumn. The flower bulb grower mulches the rows or beds of bulbs with straw to protect the bulbs during the freezing winter temperatures and/or to prevent the wind erosion of sandy soil. A hyacinth, for example, would freeze during a lengthy period of severe frost.

When the plants bloom in the spring, the grower will usually remove the flowers from the plants. The most important reasons for doing so are to prevent diseases and to encourage growth. Other aspects of cultivation include fertilising, irrigating, removing diseased plants and trueness to variety, and preventing disease. The summer months are the lifting period for spring-flowering bulbs in the period from half June until half July. The small flower bulbs are then separated from the larger saleable bulbs.

Summer-flowering plants such as dahlias, gladioli and lilies, are planted in the spring. The flower bulb grower lifts these bulbous plants before winter sets in, in the period from half September until half November. The cultivation methods are generally the same as for the spring-flowering types.

Flower bulbs are stored at a wide range of temperatures. Storage rooms are kept at temperatures from -2°C to +44°C. With all these different temperature treatments, Mother Nature can really be fooled. It is possible to encourage bulb production during the next growing season, to advance flowering or to retard it, to increase flower production, and even to control diseases. These kinds of treatments are used for flower bulbs throughout the bulb sector: among flower bulb growers, flower bulb dealers, special temperature treatment companies, bulb flower producers, etc.

In comparison with earlier days, the prices for flower bulbs have not risen. This is due to the advanced state of mechanisation combined with the development of large-scaled operations. Planting, applying and removing the winter mulch, deheading of the flowers, lifting, grading and even the traditional bulb peeling are mostly done by machine. This does not mean that labour problems don’t exist, however. In fact, next to the need to improve the environmental friendliness of the growing methods, this is one of the most important concerns for the bulb grower. Every year, it becomes more difficult to find temporary workers for the seasonal harvest peaks.

Environmental management

This may well be the most important concern for today’s bulb growers. Bulb growers are aware that the opportunities for applying crop control agents will only diminish. Permission to use these agents is being withdrawn, the quantities allowed are being reduced, and the permission to use them is subject to increasingly stricter regulations. The various organisations in the bulb sector have now joined the ”Milieu platform” (an environmental consortium for flower bulb growers). Within this consortium, organisations are launching initiatives intended to approach environmental problems in a balanced way. Continued reductions in the use of and dependence on chemical agents, fertilisers and energy are the major topics being addressed. Concrete agreements (covenants) have been made with the government in regard to limiting energy consumption and the use of chemical agents. Results of the environmental discussion include: spray-free zones along the drainage ditches, spraying permits, required inspections of field spraying, modified spraying techniques, keeping fertiliser records, requiring that animal manures be injected into the soil rather than spread on top of it, the growing cultivation of organically grown bulbs, etc.

Bulb flower production

The majority of the cultivated flower bulbs are used for flower production. All the production of iris, tulips, hyacinths, lilies, narcissi, etc, has been preceded by bulb cultivation. Some of this production is done by Dutch flower growers, but a large share of the flower bulbs produced in the Netherlands is sent to similar operations in other countries. Flower growing operations are also undergoing interesting developments. We can see increases in scale, automation and new production systems. New developments include the hydroponic production of tulips, hyacinths and irises instead of soil, and the use of mobile benches. The production processes of flower bulbs and bulb flowers are closely interrelated. After all, there can’t be one without the other, and you need bulbs to get flowers!

Commercial cultivation techniques

In nature, plants usually propagate by means of seed. The cultivation of flower bulbs, however, is not that dependent on propagation by seed. This type of propagation is used only for plants that are difficult to propagate in any other way or when other ways would be far too costly. When propagating by seed, however, it is crucial that the seeds of the parent plant are true to type, i.e. they will produce plants that look exactly (or almost exactly) the same as the parent plant. Examples of bulbs or corms that are propagated by seed are anemones, Winter aconite (Eranthis), ranunculus and Tigridia.