Rose flowers droop as soon as buds fully open, why?

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julie777
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Rose flowers droop as soon as buds fully open, why?

Post: # 71433Post julie777
Sat May 09, 2020 6:45 pm

I have been searching for an answer and not found one, though I have found references online to this problem, I couldn't find any reasons or solutions.

I have some miniature roses that came from a supermarket-bought miniature, which I split and have grown in bigger pots outdoors. When it was a miniature in its original pot there was no problem, but when transplanted they look healthy and the buds are fine, but once the flowers open their necks droop as if the flower is too heavy for the stem supporting it.

I am wondering if this is because I used bags of cheap potting compost to transplant them into, which could be acidic, and I have been told that roses like alkaline soil. Maybe adding chalk or limestone, or some form of calcium to the compost would stop this problem? Maybe the nurseries who supply these miniature roses to supermarkets know about this problem and have something in the potting compost to stop it happening?

Obviously when I bought the original miniature rose pot, the flowers were all upright and perfect. Why are they now drooping as soon as the buds fully open?

I will try to solve this, and if I can't I will just have to throw all these roses away.
Zone 9.

MidAtlas1

Re: Rose flowers droop as soon as buds fully open, why?

Post: # 71438Post MidAtlas1
Sun May 10, 2020 1:10 pm

I think there is a good chance that this will self-resolve after a while, especially if it only just started happening relatively recently.

Sometimes greenhouse growers apply growth regulating hormones to produce more compact growth in plants like the ones you purchased. I don't know if that's the case with yours, but there might be an awkward phase while the plants are adjusting to their new environment. I would wait a while before taking any kind of corrective measures with respect to the potting mix you've chosen, unless you see additional symptoms that suggest a specific nutrient deficiency or excess.

Roses do not generally prefer alkaline soil; a slightly acidic pH is best for optimum nutrient availability. Plants do require calcium, but the pH doesn't actually have to be alkaline for that to be available for absorption.

julie777
Posts: 27
Joined: Wed Jan 15, 2020 4:04 pm
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Re: Rose flowers droop as soon as buds fully open, why?

Post: # 71439Post julie777
Sun May 10, 2020 1:23 pm

MidAtlas1 wrote:
Sun May 10, 2020 1:10 pm
I think there is a good chance that this will self-resolve after a while, especially if it only just started happening relatively recently.

Sometimes greenhouse growers apply growth regulating hormones to produce more compact growth in plants like the ones you purchased. I don't know if that's the case with yours, but there might be an awkward phase while the plants are adjusting to their new environment. I would wait a while before taking any kind of corrective measures with respect to the potting mix you've chosen, unless you see additional symptoms that suggest a specific nutrient deficiency or excess.

Roses do not generally prefer alkaline soil; a slightly acidic pH is best for optimum nutrient availability. Plants do require calcium, but the pH doesn't actually have to be alkaline for that to be available for absorption.
Thanks for this advice. Calcium might be more available for absorption in a slightly acidic soil? I don't know what the pH of the cheap bags of potting compost is, but some that I used was coconut coir, which could be a bit acidic, and the other bags could also be a bit acidic. I added some perlite to both. They are well fertilised and watered.

My other roses seem to be fine in this potting compost.

When I bought this miniature rose it was actually about five rooted cuttings in one tiny pot, sold as a houseplant. When outside in bigger pots they each grew into quite a big, healthy looking rose bush with a lot of buds. In the ground they could grow even bigger.
Last edited by julie777 on Sun May 10, 2020 3:48 pm, edited 1 time in total.
Zone 9.

MidAtlas1

Re: Rose flowers droop as soon as buds fully open, why?

Post: # 71443Post MidAtlas1
Sun May 10, 2020 10:48 pm

If you've had the plants long enough for them to shake off any growth hormones that might have been used in producing them for use as temporary table decorations, then there could be other factors to consider. Some roses do simply have weaker necks that don't hold the flowers upright. I would be very surprised if such a seedling would actually be knowingly selected by the breeder in this case, though.

Cool temperatures can also sometimes lead to larger flowers being produced. It's possible that by cutting back on any nitrogen-containing fertilizer (if you've been fertilizing them, or if the potting mix already contained fertilizer) might help reduce the size of those blossoms somewhat, too. If your other roses are doing well in the same mixture, that seems like it probably isn't a nutrient deficiency problem.

As for calcium availability, it does increase with increasing pH, but is adequately available above 5.5. A pH of 6.5 is normally considered ideal for most roses.

julie777
Posts: 27
Joined: Wed Jan 15, 2020 4:04 pm
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Re: Rose flowers droop as soon as buds fully open, why?

Post: # 71452Post julie777
Thu May 14, 2020 6:31 pm

That will teach me to think those un-named miniature roses sold as houseplants would make a nice outdoor plant. They come with I think a six week guarantee. I will see what happens as the plant matures, but expect to be disappointed. I bought a proper named rose, Blue for You (Pejamblu) which has started to flower and is making me very happy as it is so perfect. It makes me realise how much work must go into breeding such a lovely rose. Maybe I will stick to buying proper roses from proper breeders, not expect un-named miniatures to look nice, though I do have another rose bought as a miniature houseplant now grown in a big outdoor pot that is quite pretty and its flowers don't droop. I might have been better off spending a bit more money on buying proper named miniature or patio roses, for the amount of time I spend with them.
Zone 9.

julie777
Posts: 27
Joined: Wed Jan 15, 2020 4:04 pm
Contact:

Re: Rose flowers droop as soon as buds fully open, why?

Post: # 71498Post julie777
Tue May 26, 2020 8:25 am

MidAtlas1 wrote:
Sun May 10, 2020 1:10 pm
I think there is a good chance that this will self-resolve after a while, especially if it only just started happening relatively recently.

The second flower of this rose to fully open this year has opened perfectly, with no drooping/nodding. Last year this variety all drooped/nodded, and the first flower this year did the same.

These roses are now full of buds in various stages of opening.

I fed them some Miracle Gro and put a bit of Epsom Salt in some of their water.

They are very beautiful roses, covered in flowers all summer and into winter, but the flower size is actually quite big for a miniature. I have three varieties altogether, and it is the white ones that drooped/nodded last summer and the first flower of this summer. The other two varieties seem ok

Somebody said that miniature roses are sterile. Is this true? I suppose the bees might use them to pollinate other roses in my garden? It would be wonderful to get crosses with them, preserving their small size, suitablity for a small space, beautifully shaped flowers, amazing colours, and being covered with flowers all summer. It would be nice to cross that with other qualities, maybe scent.
Zone 9.

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