Skip to Content

When To Plant Gladiolus Bulbs: Full Guide for Weeks of Color

When To Plant Gladiolus Bulbs: Full Guide for Weeks of Color

Gladiolus flowers are a true pleasure. They have the ability to bring bursts of vibrant color to any garden, ranging from the gentle, muted shades of pastels to the rich, fiery tones.

When is it too late to plant gladiolus bulbs? Most gladiolus plants will not tolerate freezing temperatures, therefore bulbs should not be planted if they cannot receive at least three months of above-freezing temperatures. These flowers need around three months to mature and may bloom for around two weeks.

These flowers can be very simple to cultivate when you understand them. We have put together a few pieces of gardening know-how so that you can enjoy these flowers in your own home and yard.

When To Plant Gladiolus

You can begin to plant gladiolus bulbs as soon as the ground is soft enough to cultivate and the last frosts have finished. This usually falls into the beginning or mid-spring for most US residents.

Best Time To Plant Gladiolus Bulbs

The best time to plant gladiolus bulbs (for those living in Zones with frost) is definitely spring.

This also means that after all the gray of winter, these flowers will come to life and fill your garden with the much-desired colors of the new season.

Is It Too Late To Plant Gladiolus Bulbs?

You may be wondering to yourself whether there is enough time in the growing season to plant gladiolus bulbs.

Consider that plants need at least 10 to 12 weeks to reach the flowering stage, so if the first frosts fall on these dates, the growing season is already over.

Should I Soak Gladiolus Bulbs Before Planting?

No, this step is not necessary to grow gladiolus flowers. However, some gardeners do opt for this method, and there are some reports that it speeds up the time it takes the bulb to sprout.

For this method, simply soak bulbs in tap water the day before planting.

Stagger Plantings

Many gardeners, whether growing ornamentals or food crops, will stagger their planting, also known as succession planting. This method means planting new gladiolus bulbs once every two or three weeks.

What this does is ensures that there are always blooming gladiolus flowers in your garden, right until the end of the growing season.

How Deep To Plant Gladiolus Bulbs

There are a few different opinions on this topic, but most people agree that around 4 to 6 inches deep is a safe bet for planting most sizes of gladiolus bulbs.

Gladiolus Bloom Time

You should expect your gladioli to sprout within about one month of planting and to begin producing flowers around 6 to 8 weeks after sprouting.

White gladiolus up close with a wide variety of other colors in the background.

How To Plant Gladiolus Bulbs

While planting this flower is actually a very simple process, it can be easy to make mistakes as a novice — don’t worry, we have all been there!

Here is a detailed walkthrough on how to plant gladiolus bulbs;

  1. Remove the thin first layer of skin on your bulb. If it is soft or looks diseased, discard it.
  2. Select a suitable space in the garden. Gladiolus plants will grow mostly upwards, so they can be planted closer together than most plants, but they require full sun (at least 6 hours a day).
  3. Make sure the soil you are planting into drains well, is not compacted, and consists of plenty of organic matter.
  4. Dig a hole about 4 inches deep and just wide enough for the bulb.
  5. IMPORTANT: There is a top and bottom to bulbs. The top will be noticeably more pointy and needs to face up to the sky.
  6. Now simply cover bulbs in soil, pat down lightly, and water in.

Shoots should begin to emerge within three to four weeks after planting.

Planting Gladiolus Bulbs in Pots

Gladiolus plants can definitely be cultivated in pots or other containers, but they seem to prefer the natural environment of garden soil.

To successfully grow healthy specimens with lots of flowers, make sure to use a specialized, organic potting mix like this one. These mixes contain the right soil structure and nutrients your gladiolus needs.

Continued growth is also best assured with regular fertilizing and watering once a week.

Can I Leave Gladiolus Bulbs in the Ground?

Yes, if you have very mild winters, you can certainly leave bulbs in the ground.

For those living in frost-free conditions, leaving gladiolus bulbs in the soil until the next blooming season is a hassle-free way to cultivate these flowers.

When To Dig Up Gladiolus Bulbs

Gladiolus bulbs should be dug up when the plant has finished blooming and begins to deteriorate through browning and drooping foliage.

How To Store Gladiolus Bulbs for the Winter

To store bulbs over winter, simply take them out of the ground, remove the spent bulb from beneath the new corm, and let them dry for about a week.

Now, separate all the bulbs, and hang them in a mesh bag in a cool area of the house.

Alternatively, you can also place them in a bucket or container of sand, making sure the bulbs are not touching. This is a great way to keep bulbs fresh but dormant.

Related Questions:

Can I Plant Gladiolus Bulbs in the Fall?

This is possible, especially for those growers in the mildest of Hardiness Zones, such as parts of California and Florida.

Provided you allow three months before the first frost, you can still plant your gladiolus bulbs in the early fall.

How Many Years Will Gladiolus Come Back?

Gladiolus plants will regrow every year if you do not receive freezing winter temperatures. However, they grow more vigorously if lifted in autumn and replanted in spring.

Conclusion

These flowers provide a fantastic display in gardens, and they can be grown with little input year after year. They are also fairly disease and pest resistant, especially in landscapes where there are multiple species of other plants to create healthy biodiversity.