Wow - what a difference! I will have to try that the next time I cut some roses. Thanks very much for the info.

Jackie

Thank you for being so experimental, Strawberryhill. I appreciate your sharing new knowledge with us all. And, I think you're a hoot! Kim

How many mgs of Calcium Citrate are in the tabs that you are quartering. I take Cal Citrate in its pure powdered form (NOW brand, Tbsp = 1260 mg), so I need to figure out the equivalent amount to use.

Thank you so much for this information

Yes, if you get four good days out of a cut 'Radio Times,' that's a real improvement.

Jacqueline and Landperson: My calcium citrate tablet has 250 mg of calcium, so 1/4 of that would be 62 mg, mixed with 1 cup of water.

Make sure that your roses OPEN FULLY before you add calcium. All calcium tablets have some sodium in it, and you want the cut flowers to soak up water, and OPEN FULLY, before tighten up cell walls with calcium.

I cut Mary Magdalene as a partially opened bud, threw half a tablet at 125 mg per 1 cup water. That was too much, and I jammed its stem with solutes. Mary drooped instantly, refused to open, and I discarded it on day 1.

Epsom salt made a stink-bomb out of partially opened Radio Times. So I replaced its water with calcium to perk up the bloom (yes, the petals became rigid instantly with stronger neck). However, I acidentally induced balling on Radio Times, either through Epsom salt, or fixing with calcium before the bloom opened fully. So I replaced with tap water, and Radio Times finally opened.

Conclusion: water moves best into bloom to open the petals, when there is NOTHING mixed in, or no solutes to jam the stem. Calcium is good for making the petals and the neck more rigid, after it has FULLY OPENNED with plain water.

Wowsers! News you can use! Thanks so much!!

Kay

That is really impressive. Thanks for posting the information and the pictures.

I have not located the original posts supporting this idea, but I do have to wonder if something else is going on. As a plant physiologist, I have trouble believing that you could get enough calcium into a cut flower, in so short a time, to make any difference. On the other hand, the citrate could be used by the flower as a source of energy, and we know that helps -- commercial flower preservatives almost always have citrate in them for precisely that reason. Also, those preservative solutions almost always strongly acidify the water, which makes we wonder, again, about a calcium-based substance that would at best be neutral pH, but in most cases, alkaline. So I'm wondering if the effect being seen here may be due to the citrate. That would still leave the question of why Tums works (CaCO3) -- I tend to doubt that it does, but as I said, have not found the reference about it.

Over the years, we've done quite a lot of research on floral preservatives. Generally the often-recommended aspirin has no effect at all. One of the best materials we ever found was one part Sprite (regular, not diet -- you want that high-fructose corn syrup!) to 3 parts water, then with a couple drops of Clorox in a quart of the solution. That mixture gives excellent life to cut flowers. Sprite has citric acid (Hydrogen citrate), simple sugars, and is rather acidic -- the three things we want in a preservative solution.

Malcolm, I link one of several studies where various calcium salts in the vase water or sprayed on the flower affected botrytis petal blight and/or vase life. Apparently it's the calcium ion per se, and not, in these cases, anything to do with pH.

Here is a link that might be useful: calcium sulfate etc.

I tested both the calcium solution and the Epsom salt twice with litmus paper. They both are neutral. At ridiculously high concentration of calcium citrate and Epsom salt, the Epsom salt came out slightly alkaline. This surprised me, since Epsom salt is 10% magnesium, and 13% sulfur. Epsom salt gave Radio Times' leaves a tinge of yellow.

As a firming agent calcium chloride (extracted from limestone) is used in canned vegetables, in firming soy bean curds into tofu. There's Grafting Paste (white limestone paste) for sealing cuttings: Take cuttings from plumeria, seal the cut end of the parent plant with grafting paste. It has an anti-fungal quality and prevents moisture from getting in the cut end. This is White Limestone Paste from Thailand used in both Thai Cooking and Thai Desserts. Used to make crisp vegetables and in batters for fried foods and pastries."
Gypsum, or calcium sulftate, also serves purposes in the food industry as a firming additive.

Gypsum has actually been used for more than 2,000 years as a tofu coagulant and can also be used to stiffen flour-based dough. Calcium sulfate can be used to keep fruits and vegetable firm by bonding calcium to the negatively charged carboxylic groups in pectin present in the food to increase the water-holding capacity.

Thanks Michael for the reference and comments. I can see that it could affect Botrytis, but in the photos above, there is no apparent Botrytis problem.

Malcolm, in the study they got longer vase life from the gypsum-infused cut roses, apart from the botrytis finding.