3,226 Garden Web Discussions | Dahlias
so many things to say about disease and under-performance!
1) change the site and the dahlia may snap out of what appears to be a disease.
2) growers always start cuttings from tubers, then grow the cuttings on to fresh tubers.
3) Myth: Disease had nothing to do with how "old" a variety is. In fact, some of the older varieties are resistant and outperform the newer hybrids. Disease is spread by insect vectors like aphids and leafhoppers - any sucking insect that passes this on from leaf to leaf.
4) some dahlias look fine, but are carriers of diseases like mosaic virus and others.
5) later sprouting varieties will perform poorly if they are shaded out by earlier sprouting varieties, so plan your plantings by this and by height.
6) some dahlias need a bit of shade - primarily reds, which can fade in full sun.
7) feeding can help chlorosis tremendously and help the plants be more disease resistant. nitrogen early on, then potash for the flowers. try to avoid too much phosphorous. kelp meal or liquid seaweed fertilizer works wonders.
i grow dahlias for fun and because i am a dahlia addict! :)
My main problem is not disease but rather open centered blossoms during hot weather. I've acquired some varieties for this season that are suppose to be more heat tolerant so hopefully that will help. I may also set up a large shade structure as that seems to be helpful in regions with intense sun.
I've personally observed that some varieties really are more prone to having open centers during hot weather. I grew Touche and Purple Joy under exactly the same conditions and almost all of the Touche flowers were useless whereas the Purple Joy blossoms were almost all very well formed.
It's still a little early to tell but I've seen a few sprouts appearing so I know that some of my outdoor clumps survived this past winter. This was one of the coldest winters here in recent memory with a low of -4F. Most winters we rarely dip much below 10F. The plastic I was using to shed water off the bed was old and started breaking up part way through the winter which was not so good.
I also tried a different method with a bunch of spare clumps that I didn't really care about. I dug the clumps whole, labeled them and then just tossed them all in a mound on a slight slope. Then I piled dirt over them and covered with sheet plastic. I've seen some sprouts coming out of the mound this past week.
I take cuttings when the shoots are 2 inches tall. They take about 12 days to root well and can be planted in the ground after about 21 days. Tubers vary tremendously in how long they take to put out two inch long sprouts. Some do so while in storage and others take a couple of weeks of sitting in warm pots under lights. If you plant a rooted cutting in the ground at the same time as you plant a tuber in the ground, the rooted cutting will bloom 2 to 3 weeks earlier than the tuber. So, long story short, you probably have some time to take some cuttings and you will definitely have lots of flowers from the cuttings. I grow over 1000 dahlia plants from cuttings each year.
If the plants are spindly, they are not getting enough light.
Do you have a fluorescent shop light you can put them under? (suspended 2-3 " from the plants)
All of the dahlias growers that I know, divide their tubers every year, this will ultimately give you more flowers, because it gives you more plants.
Pinching the tops of the plants is standard practice. It is usually done after the 3rd or 4th pair of true leaves. Pinching encourages lateral branches to grow out, plus causes the top of the plant to fork. The laterals, and the two forked branches should all develop flowers. So pinching gives you a bushier plant with lots more flowers.
Another standard practice is to only allow one central stalk to grow from each tuber. This give you a stronger central stalk, which produces larger flowers. If you are not concerned about size then you can allow multiple stalks, but on the larger flowering types, it can make it difficult to stake the plant.
Myself - if the normal bloom size of the flower is 3-4" or less, I let multiple stalks grow, otherwise I snip off additional stalks.
Hope that helps.
This weekend (Friday) I started hardening off my petunias, verbanas, and agastache (all in the shade) and leaving them out overnight because it's been mild but I'm hesitant about hardening off the dahlias until I know what conditions they're capable of tolerating. With heavy rain for tomorrow and highs only in the 50s later this week, I'm not even sure it's worth the effort to start hardening them off yet.
I wouldn't rush getting those plants outside. April is a wacky month. We can still get snow one day and 70ð three days later, or a frost. You never know...
As far as the dahlia's go, I hear they're from Mexico originally, so I would definitely keep them inside until it gets warmer.
This post was edited by digdougdig on Tue, Apr 15, 14 at 13:27
That makes more sense - I think I didn't read your first post correctly. If it was my only tuber, I don't think I would split it down the middle. Thats an experiment you might want to try with something you have multiples of. It seems like it should work, but â¦â¦â¦â¦..
Do you regularly take successful stem cuttings from your dahlias? I have heard that they develop into full grown plants faster than tuber-grown (by a week or two) I would think in zone 6 you would still have time to take a cutting. If you pot it up and both eyes develop into stalks, you are probably going to snip one of them off anyway.
That's what I decided to do. I potted it up whole and I'll give it some time and then take cuttings. I may even get more eyes sprouting while I'm at it.
I divide my dahlias before I store them, then start all of them inside and take stem cuttings. I don't know if it's any faster; I only do it to get more plants. That way, I can give some away to friends who don't bother digging and saving.
Our soil temp doesn't reach 60 degrees until around August so it is not an essential rule. I plant mine out once the frosts are done. When it is time to plant tomatoes it is time to put your dahlias in the ground, what ever date that is in your area. I pre-start in pots to get them up to a good size first. Doing this they will start to bloom, many in July., nearly all in August and give me 3-4 months of glorious color.
I had a sheer heaven years ago that did nothing so I ditched it. Innocence never grew or bloomed either. Purplicious is a stunner - one of my favorites. It's a workhorse in my yard.
Clyde's Choice is a HUGE dahlia and it is my experience with the 10-14"s that they take a little longer to get settled in. I have the very similar Baarn Bounty and was disappointed the first year. Only 4-5 blooms and it seemed to take forever to sprout, grow and bloom. But in the last 2 years, it has increased to maybe a dozen blooms that are long lasting bloomers, even though the whole plant cycle is not nearly as long as say Sept. Morn or Purplicious.
mandolls, 1/2 my yard was torn up 6 years ago for a new septic system, and it still looks like a construction zone. I see quite a bit settled this winter, so I have more repairs to make to certain areas. I hope yours comes together faster for you.
Now, back to dahlias...the only one on your list I'm growing is Vassio Meggos. I never give up on a dahlia after only one year...I wouldn't have V.M. if I did--it did awful the first year, but wonderful the 2nd. We'll see this year.
Looks like it
2 seasons ago I let 3 clumps in the ground which I wanted to get rid of.
One sprouted in spring and when I dug it up, most tubers were rotting and it just sprouted from the rest.
If you want to keep it you could dig it up to ckeck the clump and divide it if necessary or snip off rotting tubers
Bye, Lin
Well I would have planted it already in its permanent spot, if you know it already, but since you have confirmed it's a good a root then I think you can move it now while it is still fairly infant.
I would not take a cutting of this shoot specifically. Wait until it has grown a bit, then take a cutting off its stems or even the top of the growth if you want to promote side branches.
By letting it grow and produce food for the plant, you will get many more branches and possibly even additional shoots without stressing out the one tuber that is trying to regrow based on its own stored energy.
thank you both, soil is at 9ðc in someplaces and around 13ðc in others, I planted (wilkos (local basic home diy store) ones that are basic colours for cacti one's for a pound, and they have not sprouted yet they was planted about month and half ago.)
I will let them grow more before taking cuttings.
the spot is going to be along that fence that gets Sun all day everyday even in winter (but I'll dig up for winter)
thabk you Leo
If they are not dry husks, or piles of mush - then they are probably good to go!
They need warmth and a little moisture to eye up and start to sprout. I put my tubers in domed trays, lightly covered with moist potting mix, and put them on top of the fluorescent lights that I start seedlings under - Once they start sprouting I put them in pots under lights.
I can't plant out until the beginning of June here and I like to get a bit of a head start. Your growing season is probably even shorter than mine.
Hi Matt ,
I live in the midlands of South Carolina.
I didn't dig up my Dahlias for the winter.
I just cover them with pine straw.Now that it is spring I am taking some up to check or divide them .
Yesterday I already plant some of my Dahlias .
I plan to cover my dahlias with clear plastic containers this week as our forecast is for a low one night is near 39 as well.
The Dahlias I left in the ground over the winter are now coming up , here is photo .
I know i should have divided this plant but I don't really like this kind.
Larisa.
can't help with the temperature thing
but Dahlias stay sturdy if they get full sun, and little additional watering if the soil is good enough.
I water mine only if their leaves droop and still hang in the evening
flower size:
if you want giant flower heads, don't top the plants. fewer stems produce larger flowers. Disbudding would help to give larger flowers.
But then you should probably stake each stem individually.
Another part of sturdiness is genetics, cut flower types produce long stems, so the plants are rather leggy than compact.
If you have several plants of the same cultivar, you could experiment and try topping and not topping them.
bye, Lin
My Myrtle's Folly bit the dust 2 years ago...I loved that one!
Looked at another store for dahlias today...they had a package or 2 of 4 kinds...Akita, some plain red one, a dark purple red too much like ones I already have, and a pink one with white tips. That was it. A different store 3 days ago...1 mangled package of Arabian Night...a dahlia I really like but already have.
These are no longer available.