Lifting Bulbs after flowering
For many bulbs, the foliage dies down after flowering, leaving only the dormant bulb in the soil. While in this dormant state, some bulbs are susceptible to rotting, attack by pests, etc. This can occur if the bulb is not particularly hardy in your climate, or if you apply irrigation water at times of the year when the bulb is used to experiencing dry condition; this can be a problem in mid-summer especially where you are watering other perennials through the heat. For this reason many bulbs are lifted and stored in a clean, dry and dark place to protect them from deteriorating.
Bulbs and other underground plant storage organs such as tubers and rhizomes also become more susceptible to water logging and attacks from pests and diseases in cool, moist conditions. In areas that have cold, wet winters bulbs will need more regular lifting than in other places. The need for lifting also varies with the type of bulb: some are more sensitive than others and require extra care.
Once the foliage begins to die down, you should generally stop watering. Liquid fertiliser can be applied to increase the bulb’s nutrient store.
Lifting and Storing Bulbs
Let all the leaves die before you dig up the bulb. This may look untidy, but it is important for the plant to be able to store food in the bulb for next season. Some gardeners plait the leaves together to keep them looking tidy while they die back.
When you dig up the bulb or tuber take care not to damage it with the spade or fork. The best way to lift bulbs up is to push two spades into the ground about thirty centimetres either side of the bulb clump and whilst supporting it from beneath, lever it out of the ground. Wash the soil off with a firm jet of water then let the bulbs dry completely before storing.
The most effective method for storing bulbs is to put them into net bags and place them somewhere cool, dry and airy – a dark, cool corner of the garden shed is ideal. Dust the bulbs with a fungicide powder and don’t overcrowd the bag as this can encourage fungal diseases.
There are other methods to store bulbs. For example, you can layer them in dry peat, vermiculite or clean, dry sand in a mesh or paper bag in a cool dry location. Check them once in a while during the winter and throw away any soft ones. The main thing when storing bulbs is to keep them dry. The bulbs will dehydrate, and may look wrinkled & pretty pitiful by spring, but that's you want.
If bulbs aren’t lifted, flowering may decrease over the years, or worse still, the bulbs may die. With proper handling and care, bulbs will multiply and improve over the years. Remember to think about climate, the type of bulb and the general garden conditions: with these things in mind, you can achieve maximum flowering with a minimum of work.
Remember though that most common species can be grown for several years without lifting, especially in cooler areas. This includes: Alliums Babiana, Bluebells, Colchicum, Crocus, Crinum, Gladiolus, Grape Hyacinth, Ixia, Lachenalias, Narcissus, Nerines, Snowdrops, Sparaxis and Watsonia. Unless you intend to let the bulbs naturalise, they are best lifted and divided every 3 - 4 years or so, to improve flower quality. Tulips do benefit from lifting because they are more prone to disease and water logging.
Some people tie or plait the leaves together to keep them tidy and out of the way. The soil should be kept reasonably moist until the leaves have completely died back.
Summer flowering bulbs that benefit from lifting
Note: the main reasons to lift these* bulbs would be to divide clumps or to avoid extreme cold (such as deep snow). These bulbs will survive if you don’t lift them.
Autumn flowering bulbs that may benefit from lifting
- Iris (some)
Read more about flowering bulbs with our ebook- Growing and Knowing Flowering Bulbs
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