Growing Gladiolus

How to Plant, Grow, and Care for Gladioli

Pixabay

Gladiolus is a classic perennial known for its tall flower spikes and large, colorful blooms. Great cutting flowers, gladioli look spectacular in summer bouquets. Here’s how to grow gladioli in your garden.

Commonly called “glads,” these lovely flowering plants are available in a multitude of colors and typically reach between 2 and 5 feet in height. Their blooms also range in size—from “miniature” flowers less than 3 inches in diameter, to “giant” flowers greater than 5 inches across!

The taller varieties, which need to be staked, are often placed in the back of a garden to nicely complement shorter plants.

Note: In Zone 7 and colder, gladioli corms will likely need to be dug up in the fall, stored, and replanted the following spring. Find your planting zone here and see instructions for this process below.

Planting

When to Plant Gladiolus

Start planting gladiolus corms in the spring, once the danger of frost has passed and the soil has warmed to at least 55°F (13°C). See your local frost dates here.
From your last frost date to early summer, plant another round of corms every 10 days or so. This will result in continuous blooms through early fall!
Depending on the variety, it takes between 60 and 90 days from the time glads are planted for the corms to root, grow, and bloom.

Choosing and Preparing a Planting Site

For the best flowers, plant glads in full sun.
Gladioli like well-drained soil that’s moderately fertile. They will not do well in heavy, soggy soil.
Ready your garden by using a garden fork or tiller to loosen the soil to about 12 to 15 inches deep. After loosening the soil, mix in a 2- to 4-inch layer of compost or aged manure.

How to Plant Gladiolus

To ensure large-sized blooms, plant corms that are 1¼ inch or larger in diameter.
Set the corm in the hole about 4 inches deep with the pointed end facing up. Cover with soil and press firmly.
Space the corms 6 to 8 inches apart.
If you grow gladioli primarily for cut flowers, plant them in rows. It’s easier to tend the plants and to harvest the flowers.
If planted with other flowers in borders or annual beds, plant the corms in groups of 7 or more for the best effect.
Water the corms thoroughly at planting.
If you’re planting tall varieties, be sure to stake them at planting time. Be careful not to damage the corms with the stakes.

Care

How to Grow Gladiolus

Put a 2- to 4-inch layer of mulch around your gladioli to keep your soil moist and help prevent weeds.
If you get less than 1 inch of rain a week, water your plants regularly throughout the summer. Otherwise, water them moderately when in growth to keep the soil moist.
Remove the faded/dead flowers to ensure continuous blooms. Once all the flowers on a stalk are gone, cut the stalk off at about 2 to 3 inches above the soil.
Be sure to leave the plant intact so it can mature and grow the corms for the next season.

Winter Protection for Gladiolus

If you live in USDA Hardiness Zone 8, put down a layer of hay or straw for winter protection. In warmer regions, gladiolus can remain in the ground through winter, provided a hard freeze (28°F or colder) isn’t common in your area.
In colder regions (Zone 7 or colder), dig up gladioli corms once the foliage has faded after the first fall frost. A light frost will kill the foliage, but not the rest of plant. Be sure to dig up the gladiolus corms before a hard freeze, or the plants could be fatally damaged.
See corm storage tips below.

Gladiolus flowers

Pests/Diseases

Gladiolus corm rot (Fusarium wilt)
Gray mold
Viruses
Aster yellows
Spider mites
Thrips
Aphids

Harvest/Storage

Cutting Gladiolus Flowers for Bouquets

Cut the flower stalks early in the morning or at night, not during the heat of day.
Use a sharp knife and bring a bucket of lukewarm water to the flower bed.
Cut stalks with only one or two open flowers. The rest of the buds will open after you put them in a vase.
Cut diagonally through the stalks and place them in the bucket.
Leave at least four leaves on the plant in the ground if you want to re-use the corms.
Place the bucket with the flowers in a cool dark place for a few hours before arranging them in a vase.
Remove lower fading flowers and cut about 1 inch off the bottom of each flower stalk every few days.

Purple gladiolus

Digging Up and Storing Gladioli Corms

In colder regions (Zone 7 or colder), dig up gladioli corms once the foliage has faded after the first fall frost. A light frost will kill the foliage, but not the rest of plant. Be sure to dig up the gladiolus corms before a hard freeze (28°F), or the plants could be fatally damaged.

Use a spade and dig up the entire plant, grasping the top to pull it out of the soil. Avoid bruising or injuring corms while digging. Shake off all loose soil (do not wash them off) and discard damaged corms. Cut the stalk down to 1-2 inches above the corm. Save the small cormels separately if you so desire. These will bloom in 2 to 3 years if you replant them each spring.
Allow the corms to dry in the sun for 1 or 2 days if the weather agrees. Sift out excess soil and place corms in wooden flats or trays. Cure in a warm and airy location for 2 weeks at a temperature of 80 to 85°F (27 to 29°C). Remove and throw away the oldest bottom corms (from the base of the new one).
Don’t remove the husks on the corms.
Dust the corms with a fungicide (“bulb dust”) to avoid disease problems. Place dust and bulbs in a paper bag and shake vigorously.
Store the corms in paper or cloth bags, pantyhose, or old onion sacks. Stack or hang the containers so air can move among them. Store the corms at 35 to 45°F (2 to 7°C) in low humidity. A cool basement is quite suitable. Do not allow corms to freeze.
Replant these corms in the spring for another year of beautiful blooms.

Learn more tips for storing gladiolus through the winter.

Recommended Varieties

‘Candyman’, for its beautiful deep pink flowers
‘Dream’s End’, which makes a good back border plant because its flower spike is up to 3 feet tall (and it has pretty light orange flowers with large yellow centers)
‘Prins Claus’, which has white flowers with splashes of pink on its petals
‘Black Star’, which has deep purple-red blooms and reaches 36 to 60 inches tall
Glamini Glads are pest resistant and bloom in full sun or partial shade. Their shorter height is perfect for the middle or front of flower beds.

Wit & Wisdom

Gladiolus is one of the August birth flowers.
Gladioli are sometimes called “sword lilies” due to their blade-like leaves. In fact, “gladiolus” itself comes from Latin gladius, meaning “sword.”
In the language of flowers, gladiolus signifies remembrance. Learn more flower meanings!

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Reader Comments

onions

Would it be ok to plant glads with or next to my yellow onions ?

glads and onions OK?

Hi, Harlan, This is one of the few questions that we can not answer; we can not confirm a yea or nay. We recommend that you contact your local cooperative extension. Find it here https://www.almanac.com/cooperative-extension-services

Hope this helps–and let us know the answer, please!

Gladiolas and all th rest

What a volume of information!!! Wow. Thank you for all the info, tips, guidance and advice on your site. The Old Farmer's Almanac is like an Encyclopaedia of gardens, planning & layouts, plants, flowers, fruits, horticulture in general, etcetera.
Thanks once again.

thinning out glads

I have one small garden dedicated to glads. I live in Zone 7 but my house is white vinyl siding and faces due south. I have never dug them out and they keep multiplying and I get many blooms every year. I have 3 colors right now. The baby ones bloom later in the summer it seems. I thought perhaps I should thin them, but with so many blooms and such good health, I hate to disturb them!

Becoming a Gladi expert!

Totally fabulous , informative article. Thankyou very much.
Everything I needed to know about Gladiolis ! I'm in my 3rd year of growing them ( UK ),
They are multiplying, so hopefully moving forward I may lift them, & plant more out unless as you say they are weak? But, you never know . I like to experiment.
They are such spectacular blooms.
I think I'm going to have to get more colours.
I didn't lift mine, and expected them to rot, but seemingly not.
It was 2 free bags of corms I had, as my mum hadn't planted them, so all in all it's been great planting experience as I expected nothing !
Viv hg.

gladiolus

I don't pull my Glads in the fall, and this year I noticed I lot, I mean a lot, of small shoots coming up right alongside the main shoot on most of the returning ones. Not all of the one returning have these shoots. They are all planted in the same area. It looks like they are small Glads trying to come up, if so, there are way too many of them, and can't be doing the plant any good. I don't know what they, are and if they are good or not.

I've looked at hundreds of pictures, and have not seen this problem/blessing shown.

Can someone help me?

baby glads

They are, as you surmise, baby glads, which are not necessarily glad tidings. The bulbs create baby bulbs; had you lifted them last year you would have, or could have, knocked these off. They seldom mature to fulfill bloom expectations. You can dig them up, discard the small shoots and see how the “mother” looks, then replant it or plant new bulbs.

Eaten Sprouts.

My little sister's dogs ate the tops of my recently sprouted Vista gladiolus and my recently planted rose bush. Is there any chance of them re-growing in a few weeks, or are they goners?

Sprouted Gladiolus

Hi James,

There’s a chance they will grow back in, but it depends on how bad the damage is!

first frost coming... still flowers blooming

I live in Canada and we are forecast to have our first snowfall, with temperatures at well below freezing for a few days. I still have several glads that are about to put forth flowers. Should I cut all flower stems and then dig up my bulbs despite the fact the plant has not "died off"? Thanks for any info

Awesome

These are really pretty interesting in taking care of gladiolus. Thanks for sharing your insights and tips.

Neon Green Glad's!

I dug up some of my Mom's Glad's when we had to sell the home after my dad's passing & my mom was put into a Memory Care Home. So far I have Purple, Pink, & Neon Green Flowers. Not Yellow! Nowhere have I ever seen the Green Glad's nor has anyone I know. My Mom's are the only ones! Is this unusual?

after the first year my glads

after the first year my glads just grow good green leaves? no flowers. i do not dig them up each year is that a problem?

Gladiolus leaves but no flowers

Usually, the reason you get leaves without flowers is because 1. bulbs have been overfed with with a nitrogen fertilizer (or lawn fertilizer) which encourages leaf production sometimes at the expense of flowers, or 2. bulbs are planted in too shady or wet of an area. Most bulbs need at least 6 to 8 hours of sun and soil that drains well.

Another possible reason is that the bulbs leaves were cut too soon the previous year. Bulbs need the leaves even if the blooms are done. The leaves collect nutrients for next year. Once the leaves yellow, they may be removed.

Finally: If you have been growing these bulbs in the same area for many years, they may need to be divided. Bulbs can be dug and divided once the leaves yellow this spring. Replant soon after digging. No need to wait until fall to replant.

cladiolias

I planted glads and spikes came out but got broken off by watering it
will it still grow

Zones

Why can't I find a map showing the zones you are talking about? I am not sure which "zone" I live in.

USDA Zones

The zones in question are those defined by the USDA. Find a map here: https://planthardiness.ars.usda.gov/

Gladiolus

I received a stem of gladiolus with my Mother's Day bouquet of flowers and would like to plant it, how do I do that? Is there anything to need to do to prepare if for the dirt or do I just put it in dirt. I'm not good with flowers of any kind at all, but these are so beautiful I would like to keep it growing.

I live in the very south, my

I live in the very south, my gladiolus stay in ground year round. They now have multiple small shoots around each original plant. Do I need to thin them? The larger plants have beautiful flowers. By late spring the bed looks like it needs mowing.

Gladiolus

I live in southern tip of Texas, zone 9b. I have never grown glads in this kind of climate. It is January 5th and most of my glads still have green leaves. We may not get even a light frost here. Do these need to be cut back before spring growth? Please advise.

Glads in zone 9

Do not cut them back; the flowers bloom on the stems. No stems, no flowers. We are finding sources that assure that glads will thrive in zone 9, perhaps none better than the Galveston County office of Texas A&M’s Agrilife Cooperative Extension. They produced a 100-page booklet and a search for “gladi” in it brings you to Chapter, 5, page 49: https://aggie-horticulture.tamu.edu/galveston/publications/Creating-the-...

We recommend that you reach out to folks there; you can find them here https://www.almanac.com/content/cooperative-extension-services Click on Texas and numerous options come up (we clicked on “AgriExtension” at the top, and in the middle of the page pops up a button for asking questions.

We hope this helps.

gladiola

My tallest glads this year have grown to a height of 7 foot, they had plenty of water in heatwave. and the colours were vibrant. 90 days from planting six inches deep to flowering.
all fed Epsom salts and home made compost.

giant glads!

Seven feet tall?! Were they a particular variety? That is amazing! No doubt your “formula” worked magic on them! Thanks for sharing! Although we can not post pics here, we’d love to seem them on Instagram if you tag TheOldFarmersAlmanac . Cheers!

7’ gladiolus

Hi. First of all congratulations on your 7’ glads !! I am utterly in awe & would love to see pics if u could show me these beautiful flowers uv grown!! I must learn your secrets to grow them here for my mother!! I live in Central TX out in the country & my mother’s fav flower is gladiolus. I have tried to grow them 3 years in a row with poor outcome!! this year will be the first year I have been able to actually cut a flower for the table, I have planted hundreds of bulbs!! I have used a variety of planting spots to see what if any area is best. I have tried full sun part sun ground soil potting soil and miracle grow food I have tried potting the.bulbs as well! I’m so frustrated that out of so many bags of bulbs i have only produced one beautiful red gladiolus that was breathtaking... the rest are either of poor health dismal color or get eaten.by our annoying grasshoppers before I ever see color bloom!!! Some are curled when they come out of the stalk and don’t look good at all & others the flower itself dies before ever blooming!! This is exasperating as I want so badly to produce multitudes of fresh flowers daily or weekly at least for my 80 yr old mother!! I feel like she may pass away before I ever get to spoil her with bouquets of fresh gladiolus on our table!! Please help! Thank you!

gladiola

I see the remarks about glads being called the sword lily.

may I add to that, the Romans had a short sword called the gladius. look up wiki.

My gladiolus leaves are 30 to

My gladiolus leaves are 30 to 35 in., no stems yet
And no sign of them either. What would you suggest?

glads

Hello, glads bloom by color, meaning certain colors will bloom first in the garden. August is usually when they start to bloom, and when it happens, it seems to happen v ery quickly. All of a sudden you will notice a flower spike that you hadn't noticed before. They are worth waiting for.

Glads in Summer!

I transplanted my Glad's when we moved in Sept. or Oct. 2018. By March 2019 they were already starting to bloom & all were finished well before Summer. I live in Houston, TX. & they are under a small Japanese Maple, yet get lots of Sun. I need to find out when to plant more Corms to get them to bloom all Summer!

Gladys

My gladiola has two stems on one plant!

Glads

Trying to figure out if all this extra stuff that has came up around my gladiolus is more glads or just grass .