Glorious Gladiolus: How To Plant, Grow, and Keep Them Blooming

Gladiolus are a popular cut flower, but they also make for a beautiful addition blooming in just about any garden. They are quick growers that produce beautiful flower spikes in every color under the rainbow. Their unique shape offers a gorgeous linear contrast to many different flowers, and their varying size options make them ideal for planting both in the ground or containers. 

An Introduction to Gladiolus 

While we do call Gladiolus bulbs, they actually differ slightly from a true bulb. Gladiolus are grown from a corm, which is a swollen, underground plant stem. True bulbs have visible storage rings when cut in half, but corms do not. 

One of the most wonderful aspects of Gladiolus is that they multiply exponentially. One big corm will produce anywhere from 30 to 100 cormlets in just a year’s time! This means that you can fill your garden with gorgeous blooming Gladiolus quite easily. Given how quickly they multiply, typically, they are grown in pretty large volume, which has created a bit of competition in the marketplace. The benefit to you, the buyer, is that they are quite economical! 

When grown in warm enough climates, Gladiolus will overwinter and come back the following season, but they do have a few particular needs.

How To Have Gladiolus Blooming In Your Garden All Summer Long

Gladiolus are what we would call ‘temperennials,’ which means that they are perennial in some areas but not in others. Typically, they will come back year after year in warmer climates but will act more like annuals in the cooler, more northern zones. With that said, regardless of where you are planting them, you can definitely enjoy them all summer long! 

Blooming Gladiolus, while beautiful, have a reputation for growing a little leggy and falling over. There are a couple of different ways that you can prevent this. The first is to ensure that you plant them in full sun. While there are some plants that don’t mind the shade, Gladiolus will have a harder time blooming if they are not in full sun. 

The second tip to help keep your beautiful blooming Gladiolus upright is to ensure that you plant them deeply enough. Typically, we recommend planting them at a depth of about six to eight inches. 

Since Gladiolus grow very quickly, they should get at least half an inch of water per week, and we recommend utilizing a soaker hose versus spraying them with a traditional hose head. Also, compost-rich soil will help retain moisture which means you will not have to water as often.

Fertilize your Gladiolus when you are planting them as they need enough time to get those nutrients down to the root level for it to be truly beneficial.

How To Keep Your Blooming Gladiolus Healthy

When grown in warm enough climates, Gladiolus will overwinter and come back the following season, but they do have a few particular needs. One is that we find they prefer to sleep in a dry bed just like you and I. This means that they need to be planted in well-draining soil. Otherwise, if they stay wet while dormant, they are likely to catch a fungus and rot. We do not recommend using chemical controls because we believe that they can be avoided simply by growing our flowers in good, healthy soil. 

When planting your Gladiolus, be sure to provide enough space between them as they can be susceptible to thrips. These are tiny little insects that are difficult to spot with the naked eye. While you won’t likely see the pest themselves, you will find that they damage the plants, which most often shows up in the form of brown leaves. If Gladiolus are planted too close together, it makes it easier for thrips to spread quite quickly. 

Prevention is the best medicine when it comes to dealing with a pest like thrips. So, in addition to providing adequate space for your Gladiolus, give them a bed of lots of good, organic soil, and avoid over-fertilizing. Nitrogen promotes leaf growth, so often, when you see plants that are not blooming well but have a lot of leaves – it’s a pretty good indicator that you might have too much nitrogen in your soil. The excessive leaf growth occurs as cell walls become elongated, which annoyingly makes those plants more attractive to pests like thrips. 

Another way to have beautiful Gladiolus blooming in your garden all summer long is by planting them sequentially. Given that they are relatively affordable, if you split your corms up into, say, 10 different groups, you can plant them a week apart, and they will bloom one after the other all summer long.

Some Of Our Favorite Blooming Gladiolus 

There are many Gladiolus species that we absolutely love growing in our gardens here at Brent & Becky’s. Gladiolus callianthus, also known as Gladiolus Acidanthera or Abyssinian Gladiolus is a particular favorite of mine. 

Gladiolus callianthus are somewhat late-blooming and don’t have as many florets as some of their larger counterparts. But, their florets bloom in a beautiful white with a burgundy center, and their fragrance is just lovely. They are the first registered heirloom plants of their genus, so if you are a fan of growing older flowers in your garden, these are a great option! 

There are also a number of selection species that are quite lovely. Typically, they grow between 17 and 24 inches tall, but there are more compact varieties that will only grow to about 12 to 18 inches. 

One of our favorites, Gladiolus primulinus ‘Atomic,’ blooms for nearly a month in the heat of the summer. Gladiolus callianthus is another that tops the list for us in this plant family.

Gladiolus Rose Supreme is another absolute beauty. When blooming, these Gladioli bring a warm, rosy-salmon tone to the garden. Or, if you are looking for a unique variety, ‘Green Star’ blooms are an unusual, almost lime green shade.

Glad you stopped by? Glorious Gladiolus make for wonderful companion plants and bring a beautiful array of color to any garden, container, or vase. We hope you will enjoy planting and watching them bloom this summer as much as we do!