Below is the link to the You-Tube that showed the best top growth and root growth of lettuce seedlings, after 3 weeks in hydroponic soluble fertilizers. The best result was with high potassium (regulate osmotic pressure), and calcium nitrate, plus magnesium sulfate. Berndoodle, a past CA poster with incredibly loaded roses, once stated that clay soil is high magnesium, and calcium is all that is needed. She's right, my clay soil is tested very high in magnesium, but a tiny bit deficient in calcium, although I'm next to a limestone quarry. Calcium deficiency causes shoot-tip necrosis, and is needed for cell and root multiplication. It gives strength to cell, and helps to de-salt the soil. Gypsum is hydrated calcium sulfate. Here is a link that might be useful: You-Tube on best ratio for soluble fertilizer

Hi, There is a difference. Explain to the farm co-op what your intentions are and that you need a water soluble calcium nitrate. They may call it either greenhouse or technical grade calcium nitrate. If you buy stuff that was intended just to be thrown into a garden or field it won't dissolve that easily and you will probably end up with a gunky mess. If you buy calcium nitrate from the co-op make sure it's intended for what you want to do. Different grades of chemicals exist based on purity. For hydroponic gardening you don't need to worry about using anything extremely pure. People working in the cosmetic and pharmaceutical industries however need to buy higher grades. Chances are the chemical store gave you the price of something more pure than you need. Here is an explanation of some different chemical grades. You can always ask what grade of a chemical you are buying and the seller should be able to tell you. http://secure.sciencecompany.com/Chemical-Grade-Designations-W53C665.aspx

Calcium nitrate is the standard used in hydroponics. But otherwise, yes, calcium acetate will also do the job. Be aware that both chemicals, but especially calcium acetate, will gradually raise the pH of the medium.

Cactus Joe in PNW posted the most deep, vibrant pictures of Austin Roses: Deep yellow Jude the Obsucure, deep pink Eglantyne rose. He put all the info. on how he did that in his Gardenweb member page. Thank you, Catus_Joe, for sharing your experience, much appreciated! Here's an excerpt from Cactus Joe on how he grew his roses in container. 1. POTTING UP CONTAINERS Growing media: I use Sunshine #4 soilless potting mix. To this I add water absorbent polymer crystals (according to instructions), 3 fistfuls of bone meal to every 15 gallons, Osmocote (according to instructions), and 1 part in 3 of composted bark mulch. Feeding: I provide this with soluble fertilizer (Miracle Gro) at least once a week later in the season - usually starting from July (the Osmocote I use has an average release time span of 4 months)). The containers are mulched. My experience is that a single lapse in allowing the growing media to dry out could set the plant back as much as a months growth! Keep Cool In The Heat Excessively high temperatures in the growing media likely impedes growth. I get better results by taking the effort to shield the containers from being heated by the sun in the middle of summer. (I have measured temperatures as high as 50-60 degrees celcius in containers exposed to direct mid-day sun in the summer!) Good drainage is also vital - excessive water retained in the bottoms of the containers has caused problems for me with containers 3 gallons or larger. For containers of these sizes, I put some rocks, bits of bricks, whatever I can get my hands on over the drainage holes, and use a piece of landscape fabric over the rocks. My aim is to get the plants from little whips in 3 inch pots at the start of the season to root balls that will fill out 3 gallon containers by the end of the season." Cactus_Joe *** From Strawberryhill: I agree with what Cactus_Joe wrote. Last year I had 24 pots on my patio, this year I'm down to 16 pots, which I planted in the ground before winter hits. Same goal: to grow roses from band-size into 3-gallon solid root-ball for the ground. His putting bone meal makes sense, since bone meal provides calcium essential for root-growth. I agree with Cactus_Joe in putting rocks at the bottom of the pot for heavy rain areas like mine and his PNW. This step is not important for dry CA. My best result with pots was when I used Jungle Juice Organic Potting soil, with composted pine bark for best drainage, it also has slow-released fertilizer. Then I mixed 1/2 cup of Jobes Organic Fertilizer for tomatoes NPK 2-7-4 (with bone meal), plus beneficial microbes. Then I put a tiny-bit of granular gypsum (calcium sulfate), plus sulfate of potash on top. I don't put chemicals inside the pot, since the young roots can be damaged if in direct contact with chemicals. I was too lazy to soluble-fertilize, just my tap water at pH 8. Below is a 7-months old rose grown from seed, a Yves Piaget child with the above technique: Here is a link that might be useful: Cactus_Joe's member page of Gardenweb This post was edited by Strawberryhill on Sun, Nov 17, 13 at 19:08