Delphinium Blues

I need some help with Delphiniums. For two years in a row I have purchased delphinium plants in spring and for two years in a row I have watched them slowly die as the summer goes on. I have tried multiple plants in multiple locations... some with more sun, some with less and no matter where I place them - same result. Dead. I have tried Delphinium Blue Butterfly and some Delphinium Belladonna cultivar(s).

None of this would be a problem, after all I kill plants all the time, if it wasn't for the fact that blue delphiniums make me swoon! The first time I saw a massive planting of them in brilliant bloom it took me the rest of the afternoon to re attach my jaw that had hit the floor.

So now I am determined.... no matter how many plants I kill to get there... to grow brilliant blue, light and airy delphiniums.

My situation is:

1) I am in zone 6a with blistering hot and humid summers. Even full sun plants often don't enjoy the summer. I have many sunny, shady and partly shady/sunny areas where I could site these plants.

2) I have super sandy soil. I'm talking beach sand. I amend but obviously that might still be a problem as everything can drain away so easily, even the amendments.

3) I feed with slow release fertilizer (pellets) because of the sandy soil. I've read that delphiniums are heavy feeders so that also might be a problem. Perhaps there's not enough food there for them. Or maybe the wrong kind.

4) Most of the property has hosta gardens and acid loving plants, all of which do quite well. Although I haven't had my sand.. uh, I mean soil, tested, I am thinking it might lean a wee bit more to the acidic side in general.

Most of my plants in the sunnier spots of the sandy yard are purchased with some semblence of intelligence i.e. drought tolerant. So, despite the fact that I obviously don't have what it takes - either in skill or natural resources - to grow delphiniums, is there anyone who can help me with some success stories? What is the magic pixie dust recipe that will make these darn things grow? I'm willing to try anything... at least anything legal...

Photo is of one of my brilliant blues prior to flatlining. If anything, this whole experience just reinforces why I should stick to hosta but I refuse to learn my lesson :-(

This is my first time posting over here so "hi" to all. I usually hang out in the hosta section :-)

Sue

Hi Sue, You don't live too far from me. I've never had any luck with the del's either.

Well darn.

If I would be as desperate as you to please these delphiniums, I would mark the area ( perhaps the best a spot where they wouldn't get the full blast of the midday sun), then remove all the soil (sand) to a depth of about 80 cm. Then fill up with good quality lime based potting soil and compost and/or leaf mold and a reasonable amount of old stable dung or organic fertilizer

Delphiniums are known to lose their vitality after two to three years and have to be replaced by new plants.
You can also harvest the seed and when sown in autumn they can already bloom next summer.

The sandy soil you have removed could be used somewhere else in your garden to create a little hill or something like that.

Sue, I feel your pain. I've tried many times with Pacific giant type delphiniums, only to have 1 bloom stalk that reached 2', then died. I tried one of the belladonna types a couple of years ago from Bluestone, and they bloomed well the first year, but did not return the 2nd. I've come to the conclusion that our hot, muggy summers just won't do for them. The only consolation I've found is Larkspur, an annual form of delphinium, will grow well here and are available in the same range of colors. They are more delicate looking and willowy compared to perennial types, but do offer the same vertical element and cottagy effect. If they are happy with the location, they reseed well and have the virtue of returning like a perennial. For your sandy soil, just keep adding compost and it will keep getting better- humus helps your soil to hold those nutrients.
Neal

Addie I know how you feel, I have the same issues but with clay. Have been ammending the soil for years with compost and finally got one Delph to bloom and never to return. This year I am starting from seed, have a sixpack in frig right now.

Bonitin, I read your reply with interest, will watch the soil ph which might be my problem. Don't know about sowing the seeds in autumn since I'm in a colder zone. Any other thoughts?

Thanks, Chris

Hmmmmmmm, teh Pacific Giants do die after a year or two, although I have some hybrids which are still alive after a few years, in their 7th year. They have crossed with each other, and a white with black bee dwarf Fountain hybrid, and I have lots of self sets which I leave to get on with it. I tried Astolat, it died after a year, but have some others I bought as Clark's Choice from J Parkers. They were shown as a light blue with dark bees, but are the rich metallic blue purple which has been around now for a few years, and I love, and they do return although slugs do eat some new shoots, and they are not huge, but alive after a few years, the bed was done in 2002. A google doesn't show it up.

I grew D belladonna Oriental Blue from seed, they also went in the same bed in 2002. The bed is where I have later growing species Dahlias which grow tall, to 5'. It doesn't get sun in the winter, and only gets sun past midday in the summer. The Dahlias probably shelter them too, we had a very hot summer last year and I think they are still alive, it was also very dry for months. I hope they are still alive, they have self set occasionally but earlier as I cleaned the bed some were hoed out, after I composted the bed with leafy compost they stood a better chance, it probably helps them survive too. I have very poor sandy soil in that spot, and they feed only from the compost, fertiliser may not suit them. I know the species Dahlias like poor soil too.

I don't have many decent pics of those, they are hard to capture the 'blueness', this one of Clark's Choice was from last year, still surviving, it always gets some shoots nibbled when emerging so must be tasty. You can see the species Dahlias are still small at that time, they don't smother the Delphiniums but might give some cool shelter.

The D belladonna Oriental Blue, a good pic I managed, the above photo has one in the background. They vary in shade a little, I have a paler blue one amongst them.

This bed was planted in 2000, I put in a King Alfred which gets eaten for a start but manages some spikes, a pink no name which still grows some spikes, I had a Guinevere which dwindled to nearly nothing, I think it manages a little show, another with lilac and blue flowers which I got from a car boot sale, someone had quite a few and this one has remained robust. There is a newer strain called New Zealand Hybrids which are supposed to be longer living, it may be one of those but I really don't know, T&M sell the seeds. I got another dark blue one which was supposed to be named, but it was 3 together and I left them that way, one was dark blue single with a white bee, another a strange lavender colour, and a dirty looking almost black one.

These have crossed with two Fountain Hybrids I bought, a white with black bee and a pale blue with white bee, each year I get a few new plants in the gaps and they are all interesting. In the pic at the front are some of the bought ones, to the back left the two Fountain dwarfs, then around them all self sets.

This message was edited Feb 13, 2007 4:31 PM

I think it's the sandy soil that really does them in. I have super sandy soil, and can't grow them. My daughter 20 miles away, has heavier soil, and grows them beautifully in part shade. She planted the Connecticut Yankees series, and they are much taller than stated, and seed around well.


I would try amending the soil heavily, adding composted manure, and some lime, put them in part shade, and mulch well. My daughter's are heavily mulched. I do know they like the ground to be cool, so mulch is essential.

Good luck and let us know how you do.

Here's a site to make you drool.

http://www.delphinium.co.nz/index.html

Check out the seedline gallery, and the photo sections.

hmmmmmmm....And I have delphs on order to try this spring. At least I am forewarned :(

Well it sounds like I am not alone in my troubles. From what I had read, I definitely expected them to be short-lived but I was anticipating a couple of years instead of a couple of months! I guess those of us with sandy soils are not going to be winning any flower show prizes for our delphiniums any time soon.

Nevertheless, I think I am going to pursue the "delphinium pit" suggestion (thanks for that idea) and replace a large quantity of sand with the right kind of amendments. Need to look into the ph thing more. I think it will be important to find the right site.

Fertilizer... no extra fertilizer? I keep reading that they are "heavy feeders". A good rainstorm can wash nutrients right through the sand. I can actually watch top dress moving through the sand in spots where I've done that. All I have to do is wait for a few rainstorms and dig a hole. I can see the top dress absorbed in the sand below. But some people neglect them with no problems? Hmmm.

Mulch mulch mulch. I am a big mulcher (because of all of the sand) and have massive piles of mulch (four huge truckloads worth) composting in the back yard now for next season.

Larkspurs - I love the Larkspurs and I have got to give them a try this year! I don't really do annuals but I keep getting tempted.

Love the photos! Everyone's photos are making me dream in blue again!

Any more thoughts, please keep them coming!

Sue

I'm going to have to disagree with the Sandy Soil being the biggest problem. My Mom lives in a town named Sandy- because the soil is almost totally sand. She has grown beautiful delphs and had one plant live for 6 or so years. We have very alkaline soils here and I think they must like them because I've had very good luck with delphs myself even though I have very clay soil. We also have little humidity in summer so that might be part of it too.

Now, I'm not trying to make you feel bad. I'd LOVE to have blue hydrangeas and to be able to grow any sort of azalea or rhodie but our alkaline soil makes it completely impossible to have those things. I hope you get your issue with delphs sorted out but know that at least you made me value my alkaline soil for about the first time ever!

Finally I've discovered some other folks who can't resist the Delphinums! I purchased one in a pot about a month ago and have enjoyed watching the buds develop into beautiful blue blossoms. I will try transplanting it to my garden when the weather gets warmer. I have also planted some Delph seeds in 4" by 4" pots. They are now 10" - 12" tall and very skinny. I guess I should have pinched them when they were smaller...I want them to bunch out. Is it too late to pinch them now?? What am I doing wrong? I MUST learn to grow Delphs. I see them in blossom every time I go to town. PLEASE HELP ME!
Joyce

Is anyone here in Florida that has had luck growing Delphiniums??
Joyce

Delphinium ajacis (flora of N.America has changed this to Consolida ajacis I believe) grows wild here in Alabama. In N. Alabama on limestone Delphinium tricorne and D. carolinianum as well both do well. Not as showy as the giant ones out west but beautiful nonetheless. Two of these are blue and pretty spectacular as you noted but they don't hang around long after blooming in spring. With luck they reappear for a few years.

Remember that i down in zone 9..but we always put the perennials that we can grow in the ground in the fall. We can put them in early in the spring, but they never bloom as well. This past fall I grew from seed the Sublime Series of Larkspur from Johnny's Selected Seeds....they are growing in the ground now....planted back in late November..I will let you know what they do. I do have a good friend who owns a nursery here and she grows delphinium like crazy......I am growing in blackland clay farmer's soil.

Guys, Having had numerous problems with my plants - including killing a lot of delphiniums myself; I have discovered the following. (I live on the Outer Banks of NC - lots of hot sun in my yard & sandy soil - though not completely sandy.) I read this book on Lasagana gardening and sort of revised the idea for my own beds. Since I have extra cinderblock, I use those but you could use almost anything. I lay out the shpae of a new bed with the cinderblocks; Then I fil the bed with all kinds of garden excess - leaves, pine cones, cuttings, you could use some raw compost. Once I have built up a few inchces I cover the whole thing with cardboard boxes - yep, this keeps any weeds from the bottom layer from growing through. Then I add a few bags of potting soil on top. Any weeds at the bottom eventually die; the cardboard will gradually degrade and in the meantime the plants that I plant on top seem to do much better than anything I try to put in the ground. One of my raised beds actually has heucheras and penstemons growing in it, even though I have killed them everywhere else. It's a lot easier than digging down, and on those occasions that I do weed these beds I can do so by sitting on the concrete blocks. Just a suggetion.

Serene: Your idea sounds great! Thanks for sharing it. I will try to do the same and plant some more delphinium seeds...as well as other flowers. Do you think I should pinch the delph plants that are now 10-12" tall??
Joyce