Planting Flower Bulbs
To achieve optimum flowering results, it is important to plant the bulbs at the right time. Flower bulbs that bloom early – from January through March – should be planted in the period from September through October. The best time to plant the ones that bloom later (March through May) is from October through November.
A number of planting techniques can be used for flower bulbs.
- One is to lay out the bulbs evenly over the location being planted. It would be advisable to start by laying out the bulbs at the proper distance apart; this will prevent unwelcome surprises when you come to the end of the border. Before the bulbs are laid out, the soil should be thoroughly loosened to a depth of 10 inches. Next, you can simply plant the bulbs and they can easily root.
- The easiest planting method uses a raised planting bed. After laying out the flower bulbs, cover them with a layer of soil about 4-6 inches (10 to 15 cm) thick. After planting, the planted area should be evenly raked and then possibly mulched with organic material 1-2 inches (2 to 3 cm) thick. This will keep the soil from drying out, freezing or panning.
- If you want a more natural look, it would be best to scatter the bulbs and then plant them where they have fallen.
- You could also plant flower bulbs in the grass. A piece of sod can be lifted for planting each cluster of bulbs. After positioning them, just replace the sod. Once the sod has been tamped down properly, the planting location will be invisible after a few days.
- Layered (lasagne) planting extends flowering by planting bulbs with successive flowering periods in layers. The flower bulbs that will bloom last are planted at the deepest level and the earliest to bloom in the spring will be planted closest to the surface. This method can be applied when planting directly in the soil or in pots and containers.
- A general rule for planting depth is to plant the bulbs at a depth at least twice the height of the bulb, with a minimum of 2 in. (5 cm). Not planting bulbs deeply enough results in poor rooting. The bulbs will emerge unevenly and produce short spindly plants. Planting too deeply, however, can result in rotting as well as late emergence.
Flower Bulbs Care
The great thing about flower bulbs is that they are relatively low-maintenance. Annual bulbs require no maintenance at all. Perennial bulbs need some fertilizing, but that’s all they need. No wonder flower bulbs make the perfect plants for gardens.
Enriching with fertilizer
- Annual flower bulbs need no additional fertilizing; their bulbs have already stored all the nutrients they need.
- Perennial bulbs extract a lot of nutrients from the soil, so these bulbs will need supplementary fertilizing. During the growing season, inorganic fertilizers are the best choice since they contain the exact proportions and concentrations of nutrients. They also dissolve easily, so that plants can absorb them more efficiently.
- Inorganic fertilizers should be used only during the growing season; applied at other times, they will leach out of the soil and be wasted. Also, be careful not to apply too much inorganic fertilizer; excessively rapid growth results in weak plants that are then more vulnerable to diseases and pests. Applying too much fertilizer can also burn plants.
- Flower bulbs being used for perennial displays and for naturalizing in borders and beneath shrubs will benefit from an application of fertilizer just as their noses become visible in February/March. An application of 2 kg of 12-10-18 compound fertilize per 100 m2 (109.36 sq. y) will do wonders. If you supply this in two applications with a week in between, the bulbs can absorb the nutrients better.
Flower bulbs in the grass
Grass in which flower bulbs have been planted should not be mowed until six to eight weeks after the flowering period. By then, all the aerial parts of the plant will have died and any seed produced will have had time to mature.
Deadheading and clusters
- Most bulb flowers do not need deadheading. The seedpods of botanical tulips, Fritillaria and Allium are even decorative and add visual interest.
- Long- stemmed tulips intended for perennial use should be deadheaded, however, to keep them from investing so much energy in the production of seedpods instead of new bulbs. When removing faded petals, there is no danger that these will fall between the leaf axils where they could be a source of fungal growth during wet periods.
- It is also important that flower bulbs that rapidly increase in number should not be allowed to produce excessively large clusters since this can reduce individual bulb growth. It would thus be better, once the leaves have died, to dig up bulbs that are tightly massed together, split them up into smaller quantities, and replant them.
Diseases and fungi
- Soil-borne pathogens and other living organisms can hinder the growth process of flower bulbs. By selecting the right planting material, choosing the right planting location, and providing proper care, you will get more pleasure from your flower bulbs. If, for example, you have planted perennial bulbs in a damp or shady location and you notice brown tips on a leaf during flowering, the culprit could very well be Botrytis. It would thus be advisable to cut such a leaf away before neighboring plants could be infected.