A question that many gardeners ask is how to divide bulbs without hurting the plant. The answer to this question depends greatly on the plant and its root system. Going in and trying to break up a root ball without knowing when and how to go about separating it properly can have devastating effects. However, failing to divide the bulbs can be a death sentence for the plant and other plants in your garden as well. Unkempt clumps of perennials can choke out other plants and themselves as they fight for water and nutrition from the soil.


When to divide bulbs…

The safest time to divide your bulbs would be when they are still in a state of hibernation. For most this will be fall, think September and October. If you miss this deadline though, many plants can be safely divided when the first shoots break ground during the spring.


Some plants will give you signs that they are ready for division. These signs include:
  • A decrease in the size and number of blooms
  • A lack of growth in the center of the mass
  • Thin and unhealthy greenery around the base of the plant


If a plant is healthy and flowering normally, you can safely forego its division.


How to divide bulbs…

Regardless of what type of bulbs you will be dividing, you will need to cut the stalks and stems back to about 3-6 inches. After you finish trimming, follow the guidelines specific to the type of roots your plant has. Roots that are more fragile can be divided simply by lightly shaking to untangle roots as you gently pull them apart, while other more sturdy roots will require a sharp knife, shears, or even forks to pry them apart.



This category includes flowers such as dahlias that possess bulbous roots shaped somewhat like a sweet potato. When dividing these root system you need to be certain that each division has some original root and a point of growth, such as a bud.



The spreading roots include the likes of cornflowers and asters. They posses thin roots that are intertwined and tangled. These are a good example of bulbs that are generally easily divided simply by using your hands.


Rhizomes grow at the soil line or just above it; a good example would be irises. When dividing your rhizome type bulbs retain one set of leaves on a few inches of the rhizome itself. It is important to note for these plants that when replanting the rhizome needs to be situated just above the surface of the earth.



Day lilies and hostas are two commonly found plants that have a clumping root system. These are also the types who, dependant on size, may require cutting or prying to get them apart. Divide the plant into sections that have at minimum on point of growth, but feel free to leave more than one if you would like a larger plant from the start.

You know how to divide bulbs, now what?

Bulbs can be stored in an area that is cool and dry, and replanted in the early spring. They can also be replanted on the same date they are divided. The choice is yours. Many gardeners choose to winter the bulbs indoors in order to stave off hungry rabbits and other scavenging creatures.
If you are planning to replant your bulbs as soon as they are divided, you will want to accomplish this at least 6 weeks before the ground is expected to freeze. This will give your newly planted clumps time to become strong so that they are not killed by the impending cold weather.

  • Choose a cooler overcast day to divide and replant bulbs, preferably when it is expected to rain for the next few days.
  • If you find yourself with an excess of bulbs, talk to other gardeners you know who may be interested in organizing a swap. This is a great way to save some money and acquire new specimens at the same time.


To sum it all up, know your plant, know how to divide bulbs to promote a healthy plant, and you will have many years of enjoyment from your perennials. Happy planting!


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