Larkspurs (Delphinium) are a dramatic and attractive plant for the garden. But when should you cut back their towering blooms? And what advantages does pruning have for the perennial? Read on to learn how and when to prune delphiniums.
Delphiniums bloom and grow in June and July, forming flowering panicles that can reach over two meters in height. The flowers arein bees and other pollinatorsvery popular and also look beautiful as cut flowers in a vase.
These amazing flowers are best known for their enchanting blue hues, but they also come in other colors. The tall-growing perennials come in purple, old pink, red and white and beautify any garden with their rich tones. Perennial specimens bloom in early summer and are ideal for borders and beds. Annual delphiniums are easy to grow because they are smaller and bloom throughout the summer.
When should you cut delphiniums?
The delphinium is a remontant perennial, which means that if it is pruned at the right time, the plant can bloom again in late summer.
You should start pruning a delphinium as soon as the flower stalks look shabby. For best results, the flowers should be cut back a hand's width above the ground immediately after blooming. If you cut them back at this stage, you may be rewarded with a second flush of flowers in late August or September.
Cut off any flowering stems, but leave any developing side shoots. You should also not remove the remaining foliage at the base of the plant. Make sure you water the plant well after this step.
You should only start radical pruning in autumn when the plant has finished flowering. To keep the plants blooming well, you can divide them every few years in the spring.
Instructions: How to cut delphiniums
If you want more blooms, it's a race against time before fall frost sets in.
- Once the flowers have passed their peak and the first pile begins to wilt, you will need to remove the entire flower stalk. This will cause the plant to put all its energy into producing more flower shoots instead of worrying about seed production. Plus, it simply makes the plant look nicer.
- To remove the old flowers, follow a stem to the ground and cut it about 10 centimeters above. Do not remove surrounding leaves or foliage.
- The sooner you cut off the first flower, the more success you will have with the second flower. So do it as soon as possible after the first flowering.
What to do after pruning
After removing the wilted inflorescences, you should water and fertilize the plant well. So that the perennial can reassemble itself quickly, it is most worthwhile to supply it with mineral fertilizer such as blue grain. Good watering is also important for new growth, both after cutting and in the coming weeks. Water only the root area and ensure consistent moisture.
When should you not prune delphiniums?
If you want to save seeds or reseed the plant (grow new plants naturally from seeds), all you have to do is leave it and wait. The plant will put its energy into producing seeds. In this case, the spent inflorescences should not be cut back.
If you have multiple plants, you can always select the best ones for seed saving and trim the rest to encourage a second bloom.
This is what the delphinium needs to thrive
Delphiniums don't require much care when growing them. They thrive best in a sunny location with evenly moist soil. They do not like dry soil, so they should be watered regularly. Mulch is very helpful in retaining moisture and keeping the roots cool.
These plants prefer slightly alkaline soil and do not like to be submerged, preferring well-drained soil.
Further tips on how to promote the flowering of delphiniums,can be found in this article.
What other plants can bloom again after pruning?
Cutting back or removing the first flowers to create a second bloom can also work on various other perennials, such as:
- Bleeding heart
- Coneflower (tips for care and pruningyou can get it here)
- daisy
- Lupine
- Phlox
- sage
- Honorary Award
- yarrow
and many flowering annuals.
