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Do Alliums Multiply? (All You Need to Know)

A flowering plant that symbolizes good fortune, patience, and unity is the Allium. This flowering plant is sometimes called the “magic wand” of a gardener. They are edible and vibrant in color.

Be it a cottage garden filled with a myriad of plants or a modern minimalistic garden, alliums blend in all kinds of plots. Versatile and easy to plant, alliums are the favorites of avid gardeners.

It could be for ornamental purposes or it could be that someone likes a certain species of this beautiful plant. Whichever the case people choose upon, they are never left disappointed.

Do alliums multiply?

Naturally, after a few years from the time of planting the alliums will multiply. Under suitable conditions, alliums grow rapidly. Also, they don’t need to rely on any third-party and can freely self-seed. Most of the alliums germinate in just 12 weeks, however, it might also take almost a year.

The magic wand of gardeners can come in varying shapes and sizes of which we’re going to discuss a few of the well-known ones below.

Drumstick alliums:

Known for their egg-shaped flowers. They reach heights of 3 feet. These alliums grow from fall-planted bulbs. They spread easily through seeds.

Gladiator alliums:

This allium can reach heights of 3-4 feet making them one of the tallest alliums. They’re a late spring bloomer but stay blooming until early summer. They spread easily year after year.

Allium sphaerocephalon:

Commonly known as round-headed. These alliums blossom in late spring and bloom till late summer. They reach about 3 feet in height. These alliums spread a foot to a foot and a half to multiply.

Giant alliums:

It grows to almost 5 feet. They bloom in late spring to early summer. When the growing conditions are favorable these alliums will rapidly spread.

Purple sensation alliums:

The name comes from the large violet-purple globe-shaped flower. They reach about 2.5 feet in height. This allium blooms in late spring to early summer. They can be left alone for years on end due to them spreading easily.

Allium millenium:

This is a hybrid allium by a breeder by the name of Mark McDonough. It blooms in Summer and reaches a height of 1 to 1.5 feet. They spread by division every springtime.

Allium roseum:

Edible and an Old-World species that are commonly known as “Rosy Garlic”. They bloom from late spring to early summer with a height of 1.5 feet. They can get out of control due to their invasive spreading.

Globemaster alliums:

These Gentle giants reach heights up to 3 feet, they bloom very late and need to be planted during fall. They easily spread into small colonies in your backyard.

Do allium bulbs multiply?

There are over 700 species of alliums out there in the wild and most of them will vigorously spread through seeds or bulbs. 

Although many alliums don’t spread at all. But for the traditional alliums after a few years from the time of plantation, the bulbs will multiply. 

Sometimes you might stumble upon a white bulb protruding out of the soil. If you don’t want your garden to be in chaos, you need to carefully take the bulbs out. 

Do this during early spring or late autumn then peel off the offsets and replant straight away.

Normally this is the best way to spread the alliums, however, you can also do this by using the ripe seeds from the flowerheads and sowing them straight away. 

But this is a lengthy process and it can take up to multiple years before you get a flowering allium.

How quickly do alliums multiply?

Alliums are plants that almost every gardener loves. These ornamental flowering plants are hardy and easy to grow. However, these plants will vigorously multiply when not properly taken care of.

Most alliums under the right conditions will multiply and make a colony in your garden. They love the sun, so the more sun exposure they have the more they grow and spread. 

Alliums love rich soil and since they’re low maintenance, they can be left alone for years. They only need a low moderate amount of water supply to multiply. Some species of them have huge leaves that will invade your other plants in the garden. 

Once the plantation process of the allium is done, in just about 2 years the alliums will start to multiply. The approximate time for this depends on the variety.

How do alliums reproduce/multiply?

When met with the right environment, alliums can multiply without having anyone to take care of them. These are some of the hardiest plants that need a moderate amount of water to survive and they love the sun. 

Let’s look at how the “magic wand” of the gardener goes through the process of reproduction below.

Natural Reproduction:

Alliums will produce bulbs in the first year from flowering. Those bulbs will be the powerhouse for the nutrients. 

When the plant produces the flowers and stems, the flowers will take those nutrients and produce seeds. Then those seeds will be the next generation of alliums.

Seed to Seed Reproduction:

This is an inexpensive process that is the easiest approach a gardener can take to multiply the alliums. 

Just like other plants, the flowers need to be pollinated. Flies are the best friends of allium flowers.

In this process, the alliums will multiply when you take the seeds from the flowers and replant them in the soil right away. The alliums can take years to reproduce in this process. 

Bulb to Seed Reproduction:

This process of reproduction involves the bulbs that multiply after a year from the point of flowering of the allium. This process occurs naturally in the fall.

However, in this process, the owner can take the white bulbs from the soil and after cleaning the offsets can replant to their desired places. This process of reproduction is much faster than the Seed to Seed.

How to divide allium millennium?

The “Allium millennium” is a hybrid ornamental onion allium that was developed by Mark McDonough. Seeing how magnificent these alliums are let’s go through the steps on how to divide them.

Site Preparation:

The transplant site needs to be prepared at least 2 weeks prior to the excavation. This is done to make sure that the majority of weeds and perennials are eradicated. 

Avoid beds where there might occur nematodes. Clean all the debris along with the remaining weeds until the top 12 inches of soil.

Lifting the Bulbs:

The bulbs will get damaged if you dig aimlessly. Therefore, with the right tools at hand, first, measure out around 3 inches from the edge of the bulb clump. 

Then stick the tines of a garden fork into the soil 6 to 8 inches deep. After that gently give the fork a pull on the handle back towards your chest.

This will pry the bulbs loose from the soil without damaging them. Lastly, by hand lift the bulb and move them to a shaded area for dividing.

Division and Planting:

After discarding the damaged bulbs, the healthy bulbs need to be cleaned and transplanted straightaway 12 inches apart. 

To make the top bulb 4 inches below the soil surface, make the planting holes at least 8 inches deep. 

The orientation of the bulb needs to be that the pointed end faces up and the roots down. Lastly, cover the bulbs and water 5-inch depth.

Does allium reseed itself?

A plant that’s low maintenance, easy to plant, and sun-loving, these are what an allium is known for. 

These plants are making your garden come alive with their vibrant colors and varying shapes. When these are happy and thriving, they will happily reseed themselves.

These plants need no one to look after them for most of their lives. Once planted they will reseed and make a colony of alliums in your garden. 

Since they are so invasive, you need to get hands-on and make sure the seeds don’t reseed themselves. 

In order to do that you need to remove the heads or stalks of the plant as soon as they take on the color brown. A method of putting a paper bag around the time the pods will open is an easy way to collect the seeds without hassle.

Final Thoughts

Alliums are great transitional and vibrant oriental plants that are hardy and low maintenance. If kept unattended post plants, they will rapidly multiply if the conditions are well met, and take over any garden. It won’t take long, after a few years a colony of allium will be in place instead.