It's the time of year for planting bulbs for Spring flowering - one of the loveliest sights in gardens and countryside - daffodils - tulips - snowdrops - crocuses bringing some much needed colour and a taste of the spring and summer to come.
As a general rule - the bigger the bulb - the better the bloom.
Choose carefully when buying bulbs. Purchase the healthiest, best bulbs you can afford. Good bulbs are plump, firm and free from blemishes. They should also be a good size (for the type) as if they are too small they may not flower in the first year.
Larger bulbs tend to produce bigger flowers. Avoid any that are desiccated and withered, or display symptoms of mould or rot. These are all signs of damage caused by improper storage. Discard any that have begun to sprout premature shoots. Bulbs overexposed to light or warmth in storage can begin leaf growth. Their immature root systems may ultimately result in weak, floppy stems.
Bulbs are best planted in clusters. They look good under a tree, in a tub or in window boxes.
Bulbs should be planted in autumn or early winter - before the ground freezes - because they need time in cool temperatures to spark the biochemical process that causes them to flower. Every species has particular requirements regarding depth to plant and the number you should place per square foot. For example, hyacinths should be planted eight inches deep, with five per square foot, whereas tulips need to be six inches deep with six per square foot. Of course, to every garden rule of thumb there are many exceptions. Shallow plantings are a must for rhizomes and a squat tuber like Begonia. Both should be placed so that their tops are level with the soil surface. Tuberous roots must be planted at sufficient depth for their fibrous roots with stem buds near the surface.
Bulbs suffer if they are not planted deep enough.
As a general rule they should be planted at three times the depth of the bulb. i.e. if the bulb measure 5 cms (2") from top to bottom, they should be planted 15 cms (6") deep.
Deep planting is recommended for many tall-growing varieties of different species. Daffodil and Tulips can all benefit from the additional support that extra-deep planting provides. Deep planting also protects the bulb from predators - squirrels love Tulips - and from moisture loss during intense heat. Soil that contains copious amounts of sand is helpful when planting tall bulbs. The added drainage helps prevent disease and assists with the "percolations" of oxygen and water down to the rhizome.
Size is another factor affecting planting depth.
Small bulbs generally favour shallower planting; otherwise they exhaust their energy on root and foliage growth at the expense of blossoms. On the other hand, tall varieties of hybrid Tulip and Daffodil may be over stimulated by sunlight and undergo rapid division of leaf scales. Mature bulbs will break up into many smaller ones, producing smaller and fewer flowers. Tall-growing Tulip and Daffodil varieties can withstand planting depths of 1 ft. (30 cm) in beds that have been well prepared and adequately dug.
Make a hole for the bulb, either with a regular trowel or shovel, or with special bulb diggers. Remember that bulbs don't need great soil, but they do need good drainage. Chicken wire over the soil will prevent squirrels from eating the bulbs. Use bulb fertilizer and/or slow release bulb food, rather than bone meal to encourage growth. Gardeners who take the extra time to carefully deep-plant will be amazed at their results. Deeply dug bulbs divide more slowly and have to be retrieved for division less frequently. Good drainage is vital for deep-planted bulbs. Make allowance for it when preparing the soil by adding sharp sand. Plant bulbs soon after you buy them. If you must store them, do so in a cool, dry place or the refrigerator (keep them away from ripe fruits).
Daffodil
bulbs should be in before the end of November. Small varieties such as Tete a Tete and Jet Fire should be planted in holes 75mm (3 in) deep, other varieties at 15 cm (6ins) deep.
Tulips can be planted from October until the end of November in holes about 10 cm (4ins) deep.
Snowdrops can be planted as bulbs before the end of November in holes 75-100mm (3-4ins) deep, however, if possible, plant them immediately after flowering whilst still in leaf.
Crocuses should be planted before the end of November at about 50-75mm (2-3ins) deep.
Replacing Bulbs
Some bulbs, like tulips weaken after a few years and must be replaced. Others, like daffodils, get stronger. Some, such as hyacinths, even reseed and spread. Make sure you know what you are planting so that you can plan accordingly, and keep a record of when and where you plant your bulbs. Let bulbs leaves mature over several weeks before mowing. If you remove foliage too early, next year's blooms will be reduced. If you disturb the foliage of true bulbs, you will affect not only reproductions, but also the development of latent flower embryos. Corm foliage can usually be safely cut or disturbed at an earlier date.
Bulbs in different situations
Bulbs in beds
A formal bed is usually grown intensively and should be well supplemented with organic matter deposited at root level. Using your garden plan, stake out and dig the area to the depth required. Work in a mixture of mature compost or composted manure with super phosphate and bone meal for best results. Other amendments like vermiculite and peat moss are also appropriate. Place the bulbs as recommended in the prepared bed and back-fill carefully. Protect your new bed with a covering of mulch. If you choose to fertilize the surface area, select a balanced mixture, or on that is low in nitrogen and recommended for bulb planting.
Bulbs in isolated groups
When planting in isolated groups it is usually not feasible to cultivate the entire bed. A good compromise is to dig a little deeper then necessary and insert some prepared compost below root level before you place your bulbs. The extracted soil could also be combined with composted or other suitable amendments before being replaced. Fertilize as recommended for bulb beds.
Naturalizing bulbs
To achieve a casual, natural effect on a grassy area or beneath trees, take a handful of bulbs and scatter them. Plant them where they fall, using a bulb-digger. Choose hardy varieties that multiply vigorously for naturalizing. Otherwise, your plant is likely to be squeezed out by competition from existing vegetation. Minor bulbs like Crocus, Muscari, and Scilla are dependable spreaders. Drop them in holes punched in the lawn using a long metal crow bar. Hyacinth, Iris and Daffodil are also good naturalisers, but they're slower to spread, especially in dry or cold climates. To achieve reliable results, you must resist the temptation to tidy declining foliage of bulbs, particularly bulbs planted in a lawn.