When To Transplant Delphiniums [And How To]

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Delphiniums are loved in the garden for their show of color and ability to attract butterflies. If you need to move your delphiniums to a new location for whatever reason, we’ve researched the best time to do so, as well as how to do it properly.

The best time to transplant delphiniums is in spring or fall, but you can transplant them at any time during the growing season. To transplant them, you’ll need to find a suitable location. Once you move them to the new location, you may have to trim and stake them to promote healthy growth.

Delphiniums are very easy to transplant. However, you have to ensure that you don’t do it too late or too early and follow the proper steps. But don’t worry, we’ll explain how to do it in this article. Continue reading to learn more.

A delphinium blue grows in the garden, When To Transplant Delphiniums [And How To]

When Is The Best Time To Transplant Delphiniums?

Knowing when to transplant a particular flower is essential. Doing so at the wrong time can delay its bloom or even kill the plant.

The good news is that delphiniums are perennials that typically bloom during the summer months. As with most perennials, you can transplant delphiniums at any time during the growing season.

However, if you want to plan around when the plant blooms, it is best to transplant them in the spring before they bloom. Or, you can wait until after they bloom in the fall. In either case, you’ll have to work around freezing temperatures.

Delphinium elatum in white, purple and blue colors

Transplanting Delphiniums In Spring

Spring is the best time to transplant delphiniums because it allows them to get established in the new location before blooming. However, it’s important to make sure that you wait until after the ground warms up after the last frost.

Delphiniums grow best in USDA Hardiness Zones 3-7. This means that they are very hardy plants that can tolerate cold winters. However, you don’t want to transplant them while the ground is still frozen because it can be challenging for the roots to establish themselves into the soil and take up water.

Waiting until the ground thaws in early spring helps ensure that the roots have time to take to the soil. But, you don’t want to wait too late in spring either because it can delay their bloom. Ideally, you’ll want to transplant delphiniums in early to mid-April.

Transplanting Delphiniums In Fall

The term “fall” is used very loosely here because you can transplant delphiniums from any time after they finish blooming up until a few weeks before the first frost. That means you could transplant them in late summer as long as they are done blooming, or you can wait until fall starts.

As with transplanting them in the spring, moving delphiniums after the ground is frozen can affect how the roots take to the soil. If you don’t move them in the late summer or fall before the ground freezes, they will usually survive the winter, and you can wait to move them in spring.

If you waited too late in spring but don’t want to wait until fall, you can move delphiniums during the early summer months as well. However, it may delay their bloom since they usually bloom in early summer.

In general, September is the best time to transplant delphiniums in late summer or fall. But, it just depends on where you live and how soon the ground freezes.

What Should You Know Before Transplanting Delphiniums?

Blue delphinium flower

Knowing how to transplant delphiniums is as vital as knowing when to transplant them. But before you do so, here are some things you need to know.

Where Is The Best Place To Plant A Delphinium?

The best place to plant a delphinium is in a location that receives full sun, meaning six or more hours of sunlight per day. But delphiniums can grow very tall, so you have two options when it comes to planting them.

Delphiniums do best in open spaces with plenty of room to grow since they can grow so large. You can plant them in a sunny location by themselves or plant them in flower beds. If you plant them in flower beds, it’s best to plant them in the back, so they don’t shield your other plants.

Due to their height, delphiniums can become damaged easily due to wind. Plant them in a location where they can be protected from wind [such as near a fence] or build a windbreak to help protect them.

What Kind Of Soil Do Delphiniums Like?

Delphiniums prefer fertile, well-draining soil. However, they also like moist soil, so you must provide them with plenty of water during dry months.

Adding compost to the soil during transplanting can also help your delphiniums thrive. Compost provides plenty of nutrients into the soil, especially if your soil is poor or heavy.

See More: 6 Types Of Compost You Should Know

How Far Apart Should You Plant Delphiniums?

Delphiniums can grow up to three feet wide, depending on the variety. Smaller delphinium varieties can be planted one foot apart, while larger ones should be planted about three feet apart.

How To Transplant Delphiniums

Delphinium flower blooming on blurred background

Now that you know the basics of caring for delphiniums let’s learn how to transplant them properly. By following these steps, you should have no problem getting them to thrive in their new location.

Prepare The New Location

The first thing you’ll need to do is select and prepare the new location. Remember to choose a location that receives full sun and in which the plants will be protected from the wind.

Once you’ve chosen the location, dig a hole that’s twice as wide and deep as the delphinium plant. Add two to four inches of compost to the soil you removed and mix it in.

Dig Up The Plants

Dig up your delphiniums from their existing location. Make sure to dig a wide enough area around the roots so that they stay as intact as possible and aren’t damaged.

Remove the plant from the soil by reaching underneath it and loosening the roots from the soil. Do so gently to avoid damaging them, then slide your hands underneath the plant and gently wiggle it out.

Plant In The New Location 

Place the plants in the newly dug holes, and add a couple of inches of dirt on top of it. Pat it down to ensure that it is firm.

Repeat this process until the entire base of the plant has been covered. Then, water the plant thoroughly to moisten the soil and encourage the roots to take to it.

Trim Or Stake Them

If you transplant delphiniums in the fall after they’ve bloomed, trim the back by removing all but two or three of the flower stalks. Add some fertilizer to the soil to encourage growth during the next growing season.

If you transplant delphiniums in the spring, stake them to ensure that they grow straight and tall. You can also add fertilizer at this time to encourage more blooms during the summer.

Click here to see these plant stakes on Amazon.

How Do You Divide Delphiniums?

Dividing delphiniums is best done during the spring to ensure that the separated plants have time to become established. Before you divide them, thoroughly water them the day before so that the roots don’t undergo stress or shock.

Dig holes in a new location for the plants you’re going to separate. Then, cut back excess foliage from the existing plants.

Dig around the roots and pull the plant from the ground, following the procedure above. Gently pull the plants apart, being careful to keep as many of the roots intact as possible. 

Place the divided delphiniums into the newly dug holes, and add soil mixed with compost to the whole. Pat the soil down so that it is firm, then water the plants thoroughly.

What To Plant With Delphiniums

Flowers in the walled gardens of chartwell house

Planting other flowers and plants with delphiniums can offer dimension and variety to your landscape. But, they can also protect the delphiniums by providing support and shelter from wind and rain.

Because of their height, delphiniums are usually planted in the back. You can plant other tall plants in the back as well to help provide support, including

  • Hollyhocks
  • Sunflowers
  • Tall grasses

Delphiniums are often staked to provide extra support, but the stake can be unsightly. Plant medium-height plants in front of delphiniums to help hide the stake, including:

  • Daisies
  • Foxgloves
  • Irises 
  • Lilies
  • Medium-height grasses

Finish by adding shorter plants in the front, including:

  • Balloon Flowers
  • Coral Bells
  • Coreopsis
  • Dianthus 
  • Herbs
  • Phlox
  • Short grasses

See More: 30 Tall Thin Plants For Landscaping Your Garden Or Backyard

Conclusion 

It’s best to transplant delphiniums in the spring, but you can also do so in the fall. The biggest thing is to make sure you handle the plants very carefully during transplanting to prevent damage. Thanks for reading!

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