Clippings by Strawberryhill

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RE: Browning petals (Follow-Up #13)

posted by: Strawberryhill on 04.26.2013 at 06:32 pm in Antique Roses Forum

Thanks Kippy, for mentioning about horse manure as not that effective, with regard to botrytis. I checked the percentage of calcium in horse manure, very little: Here's the ratio: Nitrogen of 0.5, phosphorus of 0.3, potassium of 0.6, calcium of 0.3, and magnesium of 0.1.

The biggest drawback of any manure if the amount of salt, which NEGATES the benefits of calcium for osmotic pressure. Check out this link below: "Manure commonly contain 4 to 5% soluble salts (dry weight basis) and may run as high as 10%. To illustrate, an application of 5 tons of manure containing 5% salt would add 500 lbs. of salt."

I would get calcium as gypsum, or calcium sulfate, which has zero effect on the pH of the soil. My clay soil is already fertile, alkaline, and high in salt ... there's no need for manure. But I still need to add gypsum per my soil test's recommendation.

Here is a link that might be useful: Analysis of Manure by Ecochem Agriculture


clipped on: 10.22.2013 at 10:36 am    last updated on: 10.22.2013 at 10:43 am

RE: Browning petals (Follow-Up #19)

posted by: Strawberryhill on 04.27.2013 at 10:10 am in Antique Roses Forum

Hi Ibuzzell: Oyster shell is calcium carbonate, DOES NOT dissolve in water, neutral pH, won't do much.

My minor is in chemistry so I did experiments when I first got into roses: I was testing someone's remark that dolomitic clay grows good Austin roses (many petals). Dolomotic clay is 10% magnesium and 25% calcium carbonate.

We got non-stop rain & gloomy weather in November, yet Austin roses gave their best form in my limestone clay. In that cold & wet month I picked the blooms and dunked them in 1) Epsom salt (magnesium sulfate) 2) Calcium carbonate 3) Calcium citrate (dissolve easier)

The blooms had a harder time opening with Epsom salt solution, and the scent went from damask to sewage. Magnesium is what makes clay soil sticky.

Calcium carbonate has zero effect, can't even dissolve in my alkaline tap water. I could put more citric acid (use for sprouting), but I would need a lot to lower the pH to the point that calcium carbonate (oyster shell) can dissolve.

What happened in rainy November here: rain water is acidic, pH 5.6, which helped to release calcium from my limestone clay. But my blooms are lousy when watered with my alkaline tap water, both in form and color.

Calcium citrate was awesome for the blooms. I DOUBLED the vase life of blooms, since they retain more water. The petals became rigid, firmer, and more photogenic. Check out Radio Times and Mary Magdalene below, picked in wet & cold November:


clipped on: 10.22.2013 at 10:38 am    last updated on: 10.22.2013 at 10:40 am