Delphiniums are perennials grown for their showy spikes of colorful summer flowers in gorgeous shades of blue, pink, white, and purple. They are popular in cottage-style gardens and cutting gardens.
Delphiniums are a favorite of many gardeners, but can sometimes be a challenge. They prefer moist, cool summers and do not fare well in hot, dry weather. The plants also dislike sudden wind or rain.
Except for the dwarf perennials, most delphiniums need staking.
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Delphiniums
Are they poisonous if chewed by a dog ?
delphinium
Delphiniums are starting to grow nicely, however, noticing a shiny look to some of the leaves. Is that a sign of some disease.
Shiny Residue on Leaves
A shiny residue on leaves could indicate that slugs or aphids are present. Check out our pest pages for information about dealing with them!
poisonous to wildlife?
I live in Massachusetts. I bought some seeds this winter and am now nervous about planting them. Are Delphinium harmful to the local wildlife? Birds, pollinators, squirrels, bunnies, etc?
Delphinium Toxicity
Delphinium are only harmful if ingested, so rabbits and deer would be most likely to be affected. Generally, these animals will only take a nibble of the plant (not enough to harm the animal) and then be turned off by the unpleasant taste. If these grazers visit your garden regularly, consider covering the delphinium while they’re young (and most toxic) or planting them in a container that can be placed out of reach.
response to deer and delphinums
to: Submitted by Ann Legere on June 16, 2020 - 12:39pm
I am not sure about Lupins, but I can say I had a deer come through my flower bed. Ate all the tops out of my fuschias, roses(of course), crocosmias, violets, but didn't touch my delphiniums which were only a couple feet away.
Lupins / Delphiniums
Can you me if deer are attracted or will eat Lupins or Delphiniums? Thank you for any info you can give me. Ann Legere
Deer resistant plants
Both plant are considered deer-resistant and good choices in gardens without fencing. (Just keep in mind: NO plant is truly deer-resistant if deer are hungry enough; however, some plants are more resistant than others.)
delphiniums and frost
my delphs are well up. should I cover them for -9 degrees c.prediction?
delphiniums and frost
No worries. Delphiniums are a hardy herbaceous perennial, which means they are fully hardy down -10 to -15C and between 5 - 14F. In late autumn and winter they die back completely to bare earth and regrow each spring. Note: They do need shelter from winds and best planted in a sheltered spot away from winds. They have heavy flower heads supported by hollow stems. Also, all delphiniums need staking as soon as they have put on growth and are getting established.
Transplanting Delphiniums
How big should Delphiniums be before transplanting them from under the grow light to outdoors?
transplanting delphiniums
Kudos for getting sprouts, Jack. Height is a consideration but you want seedlings with “true” leaves, not just the two that initially appear. True leaves appear early, so if your plants have a couple to a few inches, you’re probably well past that stage. As for height, we’ve see suggestions of 12 to 15 inches but it depends on the strength of the plants. Before transplanting you also want to harden off the plants—get them used to the world. Here is some advice on that https://www.almanac.com/video/how-harden-plants and another https://www.almanac.com/news/gardening-news/time-get-tough-hardening-plants (these are about vegetables but the process is the same).
We hope this helps!
Delphiniums indoors In Houston Texas
I want to grow delphiniums indoors in a south-facing window with small period of shade from trees throughout the day .
A/C will be maintained to 80 degrees or less
Any chance of success?
Deep South Delphiniums
Hello, my wife and I really like delphiniums but we hear that they are very difficult to grow here in the coastal southeast, zone 8b. Nevertheless I purchased some and planted in good, composted soil. What tips can you give me that would heighten my chances of success? Also are there any varieties that would do better than others in this area. I realize that they would be only annuals. Thank you.
Delphinium Dwarf Larkspur
I live on the southeast coast of Florida, can I grow these in the ground in partial shade?
Delphinium (Larkspur) in Florida
Delphinium is technically a perennial, but it can be grown as a winter annual in Florida. Otherwise, Florida is just too hot and wet for this cool-weather plant to survive a summer season.
Delphiniums do need full Sun to grow but they prefer cool weather. So let seeds germinate in winter and the plant will bloom in early spring. Once temperatures rise in summer, the plants will fade and you’ll need to remove them.
wintering pot Delphiniums
I have 3 delphiniums (pale blue/white) growing and flowering nicely in a pot on the deck in SW Iowa. How should I winter them to see them grow and bloom in the Spring again?
overwintering delphiniums
As noted at the top of this page, delphiniums can be a challenge; not all grow as perennials. Many are short-lived plants. Knowing that, you could experiement: Cut them back as advised in Care above. Put them into a garage or basement and water them occasionally. Or, if you are in zone 7 or lower, lift them from the pot now and plant them (you could also plant the pot), then lift them in the spring and repot to see if they come back.
pH
There are two conflicting suggestions on this page regarding the ideal soil pH for growing delphiniums. The intro says they are alkaline-loving, but later you say that the soil pH should be between 5.8 and 6.5. A pH of anything less than 7 is considered acidic, not alkaline (basic). Please clarify what the ideal soil pH should be for successfully growing delphiniums. Thank you!
Delphinium pH
Thanks for catching that! The information in the intro is correct: Delphiniums prefer alkaline soil, not acidic. Your soil should stay on the lower end of alkaline (between 7 and 9 pH), however.
Overwintering Delphiniums
After many years of growing Delphiniums, I
finally figured out how to protect them during our often snowy winters in
New York. And I 'm gardening in very large pots on a terrace.
I don't have to lift them or bring them inside.
I just put sand around (not on) the plants so
that even as the snow melts, even if it's a rainy
winter, they have good drainage.
You can get the sand at most hardware stores.
I now lose very few delphiniums
I currently have 5 that are two years old
and 3 that are 3-years old.
They don't last forever, but if you their roots
have lots of room to grow, they can become very
tall--even over 2 years.
Some are now six feet tall, and even in containers,
they have spread to 2-3 tall delphiniums that bloom
twice each summer.
already planted 2nd year
I live in Minnesota. Last year I planted some potted Emperor Delphiniums (dark deep purple with white bee) And one or two light blues, they grew about 2ft. With at least 2 stalks. After fall was well over and just before winter began I cut all of them back. It’s finaly spring here no more snow all the snow I think has finaly melted and we have had 4 days of over 58* degrees in a row w/ no weather below 60 in the forecast.. other spring flowers are growing out of ground. Dafadiles etc. when will my DELPHINIUMS start to show some effort of growing my garden is bare.
Tall Pacific blue Delphinium won't bloom
Bought this plant in full bloom 2 years ago and planted it in a new bed with fresh deep earth and mulch. It has half a day in full sun and half a day in shade. It grows nice strong thick 5 to 7 leafy stalks growing tall to about a yard and a half tall, and puts all its growing to growing green and tall throughout the spring and summer but for the last two years , no flowers at all. How can I get this plant to produce flowers?
Deadheading
I don't know what the dead part looks like. Sometimes I think the white is dead, but other white looks like it's the new blooms starting. What is the green pod? Should I remove it. The only thing I am confident about is when the blue dries out!
Could you post pictures of the parts and what to deadhead?
Response
Sounds like to me, you did not get any pollinators (Bee’s or butterfly’s) that first year they were planted. Awe that’s sad. It’s best to plants several pollinator favorites together at the same time. To guarantee they smell and will come. Marigolds, purple hyssops, Phlox and candy tuff, they like keep in mind flowers are Regional and species by favorite. Meaning each region has specific butterfly’s and therefore each species has their favorite flowers. Check for the species that favor your region and plant their specific favorite flower .. I don’t know if it is too late for your flowers to bud.
Delphinium seed pods
Hi I bought some beautiful delphinium plants mid July. The nursery had them in the Perennial section. I hooked the informations to each plant but either birds ran off with them or ? Anyway...they all went to seed and I took all the little pods off and emptied the seeds into baggies. Now Im wondering if that was right? Should I go dump the seeds with the plant? Im not a good gardener...Ive been told non jokingly that I should not have a yard! I agree. So what do I do with the seeds? Deb
setting seeds
You could dump the seeds near the plant. Some delphs grow easily from seed, some do not. If you want to grow the seeds (or plants) sucessfully, you should test your soil. Here’s some advice: https://www.almanac.com/news/gardening/gardening-advice/how-take-soil-test
Delphiniums do poorly in acidic or neutral soil. So, if you prefer not to test at this time, broadcast lime, wood ashes, or a mixture of the two over the soil you would use for this alkaline-loving perennial. Learn more about soil amendments.
Overall, re whether the seeds will set, consider contacting the source you bought them from for information. They may be able to tell you what type they are.
Delphiniums
I have just purchased 2plants in pots is it ok to plant out now
Delphiniums
I have seen delphiniums on sale now. Can I plant out now?
Delphiniums
Hi Mary,
It’s too late to plant delphiniums now; they should be planted in the spring. Delphiniums don’t like hot, dry weather like that of the summer.
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