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' second round of blooms
It is typical of delphinium’s second bloom stalk to be smaller than the first. Take heart in the fact that you are doing everything right: Some gardeners find this a difficult plant to grow!
New foliage Yellow
I live southeast Houston and I purchased my delphinium about a month ago. I had to cut down one spike that had already flowered a week after while another was shooting up. I also managed to get rid of its cyclamen mite infection by giving it a hot water bath for 30 minutes. My question is regarding the new growth that is yellow with green veins and a lot of is drooping. The other spike is now flourishing but shows no sign of distress. I have given the plant plenty of compost and regularly bury 3 banana peels in the soil every week. Could it be that I didn't water it enough? Could it have anything to do with the very small amount of diluted urea I gave the plant two days ago? Am I applying too much neem oil? Also, what is 1 inch of rain per week in gallons?
delphinium blues
All in all, the plant has been through a lot during its month in your care: A stalk was amputated. It was soaked in hot water. Why the bananas? These are traditionally said to benefit to roses (and some dispute this). Diluted urea? Why? Neem oil? Why—does it have looper worms? (Search “neem” on this page for more on this.) Has the plant had time to get acquainted with its new home? Does it get sun? It sound like you’ve watered it plenty. Is the soil damp? If so, it’s watered. One-inch of rain per week is watering until the water soaks down 1 inch. You should just water when it is dry. Delphiniums do not like “wet feet.” We suggest that you read the care tips above and the reader comments and our responses below.
About the new growth that is yellow with green veins and is drooping: this may be a sign of an iron or magnesium deficiency and/or it could be a sign of improper pH. Do a soil test; you want a pH that is at least slightly alkaline.
You should also consult your local cooperative extension. Click here http://www.almanac.com/search/site/cooperative%20extension chose your state, and find the service nearest you. The folks here are very helpful!
Reasons
After the other stalk had been spent, I decided to cut it to make another shoot sprout later in the year. I gave it banana peels because I read that they are great organic fertilizers with high potassium and phosphorous amounts that encourage healthy blooms. I gave it diluted Urea for the high nitrogen count and Neem oil to prevent the return of the Cyclamen Mites, powdery mildew, and other diseases. I've also applied an iron/magnesium/zinc solution to the foliage per the label's instructions for faster and safer absorption. It was a very damaged plant when I first bought it so I tried to give it extra care aside from the plants natural high demands. The PH is right around 6.2.
I tried to keep the soil moist per all the discussion posts I've read but it gets very hot and windy in Houston and the plant would often dry out so fast that I wouldn't be able to keep up with it. Anyway I kept it in partial shade and watered it each time 1 inch of topsoil dried out.
The problem is that I was advised to never let it dry out but constantly keeping it moist might have let to root or crown rot. However I don't see any fungus, there's no pungent smell, and the plant is otherwise flowering through side shoots off the second stalk. I've tried to control its environment but this Delphinium has been a very challenging experiment. I'll apply some more iron application and keep the moisture level even but is there any other preventative measures I can take?
additional care...?
Our only thought is, as noted above, to contact your local cooperative extension and ask the advice of experts there. Being “on the ground” and familiar with local conditions they may have insights or comments.
Local extension
I reached out to TAMU agriculture and they were great. Thank you for all of your insights, I really appreciate it!
WHAT?
Delphiniums are very difficult to grow from seed. Buy as a potted plant at the nursery- where did you find this info? Delphiniums are so easy to start from seed, just drop them in the fall - presto your will have lost 1/2 your garden to delphs in 3 years!
Growing Delphiniums from Seed
Delphinium is a genus consisting of over 300 species–some are annuals, others are biennials or perennials. Some grow easily from seed, others don’t. Of course, those that do are a good investment!
delphiniums
do the flowers produce seeds to plant new plants?
Delphiniums
There are many different varieties of delphiniums–some are annuals, others are biennials or perennials. Some grow easily from seed, others don’t. Climate also plays a part. So the best thing to do is save some seed and sow it in the spring. Hopefully, you will be rewarded!
Fall started seed indoors
Hello,
I started some seed on wet paper towels in black styrofoam to go boxes. I started them on 9/6, once they sprouted about 10-15 days later, I plucked them from the paper towels and planted them into to a 72 cell self watering seed starter tray with a clear cover/hood. They have shot up to about 1" tall with 2 very nice leaves. They are currently in my livingroom window. I live in Beaverton OR, zone 6 or 7. My question is, with this being the begining of fall, do I dare move them out gradually now so to get them ready for winter, and if not, will they survive indoors all winter until spring? Or in other words.....HELP!!
Growing Delphinium from seed
Dont get discouraged about growing delphiniums from seed. Use fresh seeds. I put my seeds in plastic egg cartons, and put them in the fridge using damp seed mix. I have good success. They sprout in the fridge. After most have sprouted, put them under a bright light. Normal to cool room temp. Start 10 weeks before last frost date.
Delphiniums
I live at 9000' in Colorado and have had huge successes with my delphiniums but this year most of my plants were green and bushy but no blooms, although several did bloom in other parts of my gardens. What is going on??? Thanks!!
Delphiniums Not Blooming
Hi Mary,
It is possible your soil is depleted of necessary nutrients that encourage blooming. If a plant is stressed in any way, it puts more energy into root and leaf production than into flowering. Consider getting your soil tested to determine if this is the case.
Delphinum
I have 2 purple and 1 pink delphinium. All are wonderful this year, I believe they are pacific Giants. Could you recommend where I might buy a light blue delphinium plant and a white delphinium plant. Thank you.
Adding sugar to delphinium cuttings
Sugar will only speed the decay of delphinium or any other cut flower unless you also add a little bit of bleach and some lemon juice. Use commercial floral food instead. Here is an article about extending the life of cut flowers. https://www.mastergardeners.org/picks/extendlife.html
I am a certified floral designer and a Master Gardener. I would never use straight sugar in my arrangements.
Caring for Delphinium Cuttings
Thank you for this advice—we have updated our page to reflect the information!
i live in northern southeast
i live in northern southeast alaska and have a whole bunch of delphiniums, they survive very well here and it gets done to 20-30 below 0-F for a short time in the winter. i started out with sandy soil, added horse manure and in late fall, i put about 5" of straw all around the plants.
Delphiniums
i live in Northern Ontario, and just planted 4 new 2 ' tall delpinium plants
we had a big day of rain and one was sitting in a puddle of water
our earth is nice black mud, but should i uproot the puddle plant and let them dry out a bit in a pot
or let nature take its course tks
Delphiniums don’t like “wet
Delphiniums don’t like “wet feet” and if you have a puddle now it will happen again. The soil needs to drain well so we suggest that you dig up the plants and amend the soil with compost before replanting. Or move the plants to a “drier” location.
My delphiniums didn't come up this year
2 years ago I planted 10 delphinium plants. They all came back up last year and bloomed beautifully. This year I have six that did not come up. Any chance they'll return next year, or are they dead? I want to replace them if they won't return. I am in Clarkston, MI - zone 5b
There are a few varieties
There are a few varieties that are biennial and bloom every other year. If you planted 10 plants that were the same variety chances are that the six that didn’t come up this year are dead. It’s helpful to know the name of the delphiniums that you plant. You can then look them up and get details on the variety.
I bought my first dark blue
I bought my first dark blue delphinium in July and it already had four blooms on it. I had cut the flowers off when they lost their perkiness. After the blooms were gone I left the plant in it's original pot. About four weeks later new growth was coming from around the base while the original leaves,very dark green, slowly dried out and I cut them off at the base so more energy would go to the new leaves. I also repotted the plant. The new growth is triple the size of the original and the leaves are not dark green. Now a stalk has come up and the buds are growing. I noticed that in between the top buds are black fibers or very small skinny leaves. Is this normal? Should I pluck out the black fiber things? I live near Milwaukee, Wisconsin in a condo on the second floor. Any idea how to store it over the winter? I do have room in the basement that will go no lower than 42F degrees. Or do I put it in a styrofoam container with lid. And because of my potted situation, what care should I give it during the winter? Any help is welcome!
Cut the plant down to about 6
Cut the plant down to about 6 to 8 inches after the first killing frost in autumn. You can then store the pot in the basement. Just remember to water the plant a couple of times during the winter months just so that the roots don't get too dry.
Comments are to plant in
Comments are to plant in spring, can I split and transplant now in August? I live in nw Ontario not sure of the zone.
Hi, Trucia: Delphiniums are
Hi, Trucia: Delphiniums are not the hardiest plants to divide and transplant to begin with (starting from seed often works better), but if you do wish to divide and transplant, it's best to do it in the early spring, after they've had a chance to regroup over the winter. Then again, there might not be much to lose, so up to you. Thanks for asking!
I grew my first ever
I grew my first ever delphiniums from seeds and have 4 plants that are very tall and planted up against the porch rail that I use to give them support.
My question is...I live in zone 8b. Will my dephiniums come back next year or should I consider them as annuals?
For heat zones above zone 7,
For heat zones above zone 7, it is recommended that you grow them where they get afternoon shade. Consider them to be short-lived perennials in your zone or you can grow them as annuals.
Hi, I'm in Edmonton Alberta,
Hi, I'm in Edmonton Alberta, our Delphs are huge, tall, and full, we're very happy with them, except that once a season the rain or wind will pummel them or the weight of them will bring a bunch down, I didn't realize I could stake them, my question is this, if they're grown is it too late to stake them? The ones that have been knocked down from the wind, should I cut them back and see if they'll get a second bloom, if they do would I stake the second bloom? It's mid July so realistically In Alberta I'll get good weather all of August at least most of sept and some years we won't see first frost til early oct.
Hi, K-Mi: You can always
Hi, K-Mi: You can always stake anything at any time. What we mean by the advice above to stake when they are small is that this is the best way to help them get tall. But if yours get tall without any staking to begin with, that advice is irrelevant. So go ahead and stake what you have standing. Cut back what has fallen and then stake what regrows when that happens. Good luck and thanks for asking!
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