Gladiolus flowers make a stunning backdrop to any gardenscape. While they are known for their prevalence in bouquets and in flower shops, they also make a great addition to many gardens throughout the United States.
These flowers can grow to be 5 feet tall when grown in the garden. While wild varieties are shorter, they still provide the wow factor that many homeowners and landscapers are after.
However, growing gladiolus in your garden requires more knowledge and planning. Do you have to plant them every year? Do gladiolus spread?
Do Gladiolus Bulbs Multiply?
Yes, gladiolus will multiply and spread naturally. This process requires very little human intervention and leaves no room for error. The bulbs, or corms, of gladiolus, will produce new corms each season. If you live in an area that does not have freezing winters, you can most likely leave your corms in the ground over winter.
If you live in an area that dips below freezing, it is best to dig up your corms in the autumn before the freeze hits.
No matter where you live, digging up the corms allows you to separate the new cormels from the mature corms. This will also allow you to offset planting if you are hoping to have season-long color.
Another benefit to digging up corms each season is that they are susceptible to rot. Leaving them in the ground increases the chances they will get saturated with water and begin to develop rot or other diseases.
However, if you can leave your gladiolus in the ground all year long, you will notice an abundance of flowers each season as the corms multiply under the surface of the soil.
How Do Gladioli Multiply?
Gladiolus multiply by growing new, small growths called cormels on their mature corms. Their corms act as a bulb for the plant and store energy through the winter, allowing them to regrow in the spring.
Each autumn, a gardener will have to dig up their gladiolus corms if they live in a region that dips below freezing. When they remove them, they will notice small growths. These growths can be removed after the corm has dried out for 2 weeks to help prevent rot or disease from getting in where the corm and cormel were separated.
In the springtime, planting the young cormel will allow it to mature in the soil. It will not sprout in the first season, but in the second season, it will produce bold and beautiful flowers as well as grow new cormels itself!
How Often Do Gladiolus Multiply?
When making their own gardenscape, many gardeners like to expand their current flowers and plants to create a fuller garden. Adding new plants and seeds can get expensive, so relying on what they already have saves both time and money.
Luckily, for those who want to grow an abundance of gladiolus, they multiply quickly and efficiently.
Gladiolus multiplies each season. These flowers grow from a bulb-like organism called a corm. These corms store all the energy the gladiolus needs to survive the winter months and regrow in the spring. During their growing season, they will also grow new corms called cormels. These cormels will take a season to mature but will then grow both flowers as well as new cormels, making a never-ending cycle.
How Many Times Will Gladiolus Bloom?
Some flowers will continue to bloom all season long, even after their initial buds are spent. However, gladiolus will not generate new flowers after they have wilted.
A gladiolus corm will only bloom once per season; each bloom can last about two months. Many gardeners will plant their gladiolus corms at different times to help create season-long color and visual interest.
Thanks to the ease of generating new and more gladiolus corms each season, after a few years, many gardeners find themselves with an abundance of gladiolus to plant each spring. This allows them to plant them at different times, creating an opportunity to offset the bloom times.
Some corms will be much larger than others. These corms can store more energy than smaller ones, which allows some to produce more than one stalk of flowers. While this is technically not reblooming, it does add to the fullness of your gardenscape.
If a gardener takes good care of their corms, they can be replanted for about 5 seasons. During this time, they will continue to grow new cormels, replacing themselves many times over.
Will Gladiolus Survive Winter?
Unlike tulips and other early spring bulbs, gladiolus is not tolerant of cold and frosty winters. This means that if you are hoping to enjoy gladiolus for more than one season, you will need to dig up your corms.
Gladiolus will not survive the winter in most places where the weather spends many days below freezing. They are extremely susceptible to frost and need to be dug up and stored in a dry and warm area before being planted for the next season.
When it comes to digging up your corms, it is important to wait until the stalk of the flower has died and dried out. This is usually done after the first frost of the season. Once the corm has been dug up, leave the stalk and any small cormels attached to it. Removing the stalk can cause issues for the corm and leave it susceptible to rot.
Store the corm in a warm and dry space for two weeks. Once the two weeks are up, remove the dried stalk and smaller cormels and store them for winter.
How to Propagate Gladiolus?
Gladiolus are extremely easy to care for and propagate successfully. Thanks to their innate ability to grow small cormels on a corm each season, you do not have to do much to get more gladiolus next season!
When you dig up your gladiolus corm in the late autumn, you will notice a cormel, or small corm, growing on it. These cormels will grow into their own gladiolus corm after maturing. Since the corms will grow their own cormels each season, there is little work that you need to do to ensure successful propagation.
Once you dig up your corms for the winter, be sure to leave the cormels attached for about two weeks. This will give your corm a chance to dry out so you can safely separate the two without creating an opportunity for mold or rot to kick in.
In the springtime, plant the cormels alongside the corms. The cormels will not produce a flower in their first season. However, they will reach maturity and flower in their second season, so be sure to dig them up in the autumn when you remove the mature corms.
What to do With Gladiolus Cormels?
Gladiolus cormels should be left on the mature corm for about 2 weeks after being dug up for winter storage. This gives the corm enough time to dry out before removing the stem or the small cormels. If you remove them too quickly after being dug up, you leave the mature corm open for rot or other infections.
In the winter, store your corms and cormels in a safe space. You will want them to be kept dry and warm. It is best to place them in a space kept between 50 and 70 degrees Fahrenheit. However, it is incredibly important that the corms and cormels never dip below freezing as they are incredibly sensitive to frost and may not recover.
Once all dangers of frost have passed in the springtime, and the ground has warmed beyond 50 degrees Fahrenheit, it is time to plant the corms and cormels. It is best to place them about 4 inches below the soil surface. Add a layer of compost to create healthy and nutrient-rich soil to help them grow. It is important that you do not saturate the soil with water as this can drown the corms or allow the perfect conditions for rot.
Once the summer ends, and the cold weather begins creeping in, wait until the stalk has died and dried out. Then dig the corms out of the ground and prepare them for storage.
The cycle will repeat itself season after season, with each season producing new cormels!
Gladiolus are beautiful and bold flowers that grow from a corm, a type of bulb. These corms will grow new corms each season, allowing the plant to multiply quickly and efficiently.
It is best to dig up the corms each season and allow two weeks of rest before separating the mature corm and the new cormels. Store the corms in a cool, dry space that never gets too close to freezing, and replant in the spring.
How Do I Know If My Gladiolus Bulbs Are Good?
To tell if your bulbs are healthy enough to replant this spring, grab a bucket of water. Throw the bulbs into the bucket. If they float, throw them away. Rotten bulbs weigh less and will float in water. Be sure to properly dry any healthy bulbs if you are not going to plant them immediately.
When Should I Plant My Gladiolus Bulbs?
The best time to plant your gladiolus bulbs is about 2 weeks before your last expected frost date. These bulbs will take about 90 days to flower. To enjoy the flowers all season long, plant the bulbs every two weeks until July. Staggering the planting will allow new flowers to arise as others die off.