I buy the cheapest calcium tablets every year and feed my tomato plants. I have never had a case of blossom end rot so they must be helping.

What kind of soil are the roses growing in? If you feed the soil, if the soil is a good, healthy soil your plants will be strong and healthy and better able to ward off plant diseases. I have found that either of these mixtures, 1 teaspoon of baking soda in 1 quart of water or a 50/50 mix of fat free milk and water, will help control Black Spot. Contact your local office of the Purdue USDA Cooperative Extension Service about having a good, reliable soil test done and also dig in with these simple soil tests, 1) Structure. From that soil sample put enough of the rest to make a 4 inch level in a clear 1 quart jar, with a tight fitting lid. Fill that jar with water and replace the lid, tightly. Shake the jar vigorously and then let it stand for 24 hours. Your soil will settle out according to soil particle size and weight. A good loam will have about 1-3/4 inch (about 45%) of sand on the bottom. about 1 inch (about 25%) of silt next, about 1 inch (25%) of clay above that, and about 1/4 inch (about 5%) of organic matter on the top. 2) Drainage. Dig a hole 1 foot square and 1 foot deep and fill that with water. After that water drains away refill the hole with more water and time how long it takes that to drain away. Anything less than 2 hours and your soil drains too quickly and needs more organic matter to slow that drainage down. Anything over 6 hours and the soil drains too slowly and needs lots of organic matter to speed it up. 3) Tilth. Take a handful of your slightly damp soil and squeeze it tightly. When the pressure is released the soil should hold together in that clump, but when poked with a finger that clump should fall apart. 4) Smell. What does your soil smell like? A pleasant, rich earthy odor? Putrid, offensive, repugnant odor? The more organic matter in your soil the more active the soil bacteria will be and the nicer you soil will smell. 5) Life. How many earthworms per shovel full were there? 5 or more indicates a pretty healthy soil. Fewer than 5, according to the Natural Resources Conservation Service, indicates a soil that is not healthy. to see what needs to be done to make your soil good and healthy that will grow strong and healthy plants that are better able to figth off plant diseases. Vitamins are not needed. Here is a link that might be useful: Purdue CES

Our little pug developed mast cell tumors about 8 years ago. The specialist we took him to at a university veterinary school said there was anecdotal support for Vitamin C delaying the growth of the tumors. For the next five years, Pugsly (about 15 lbs.) took at at least 2000 mgs. of vitamin C a day. Ultimately, he redeveloped the cancer, but I will always believe the vitamin C delayed the metastasizing. I'm not recommending that dosage for every dog, but I still give our other little pug at least 500 mg. of Vitamin C daily, just for general health. If you give your dog too much vitamin C, they will "throw it off," i.e., eliminate it through diarrhea/loose bowels and/or vomiting. You can then back off/reduce the dosage. I buy gel capsules of time-released vitamin C (no additives) at a health food store. They are more expensive, but they are easy for the pugs to swallow. I wrap the capsule in a piece of soft cheese. They never turned it down!

Geritol (liquid vitamin) is made from Brewer's yeast (by product of beer-industry). I love taking Brewer's yeast since it's a natural food-product, rather than refined chemicals. People give NOW's brewer's yeast thumb-down due to its bitterness, but U of Michigan Medical website stated that for brewer's yeast to be effective, it should be bitter. I mix 1/2 Tablespoon of brewer's yeast with 1 cup of milk, plus 1 heaping tablespoon of buckwheat honey, and it tastes great. It really stabilized my blood sugar, and helped me to lose weight & plus extra energy. I can see why many people report increased energy with vitamins or brewer's yeast (high in B-complex, chromium and selenium). Have been taking brewer's yeast for 1 year .. hair is super thick, at 52-year-old .. it really help with healthy hair. I took Brewer's yeast initially to repel bugs & mosquitoes when I worked in the garden ... but like the extra-energy & less cravings that I kept doing it even in the winter. Folks give brewer's yeast to their pets for shiny & smooth coat of hair, plus to repel fleas. Below is U. of Maryland Medical Center on Brewer's yeast, at $8 per pound, it's a lot cheaper than vitamins & plus help to prevent colds & flu: http://umm.edu/health/medical/altmed/supplement/brewers-yeast Below link lists caution if you take medications along with brewer's yeast Brewer's yeast contains a large amount of tyramine, a substance that can interact with MAOIs and cause a hypertensive crisis Source: Possible Interactions with: Brewer's Yeast | University of Maryland Medical Center http://umm.edu/health/medical/altmed/supplement-interaction/possible-interactions-with-brewers-yeast#ixzz3Zmk9uIfc