A quick question for you. What does the label tell you to do?

Nothing on the label.

Not to discourage you, but, I tried spraying neem oil one year and it was a complete waste of time.

And, in addition to being virtually ineffective on BS, it's phytotoxic to boot and will fry the bejeezus out of the foliage if the temps are above about 85.

The brand of neem oil might have a web site. Do you know the name?

I used neem oil last year. The only rose (out of about 40) that got black spot was one that didnt get the spray. My neighbor's roses all got lots of black spot. It killed the aphids as well.

I was very happy with the result. Even using the neem oil, there WERE lady bugs, spiders, and praying mantises, and the soil has lots of earthworms, so I think that the natural predators & soil life are still there. I also grow garlic, chives, shallots, cilantro, rosemary, thyme, in the rose bed as well, bot I doubt that those had significant impact on the black spot. I think it was the neem oil combined wiht rose hygeine (pruning and clean bark mulch).

Also, my rose varieties were not necessarily resistant varieties. Most had black spot problems the year before.

The brand that I used was called "100% pure neem oil" (strange brand name) distributed by Natural Greenhouse Products. There are many brands available, some are pre-mixed, some are purified. None are cheap, but then neither were the roses. This brand might be local to this area, I dont know. I used according to instructions.

It was a butter consistency gel at room temperature, so I placed the bottle in a pot of warm water until the oil melted. Then mixed 4tsp per gallon along with 1 tsp ivory liquid dish detergent; shook well; sprayed on non-sunny days, getting all rose surfaces, leaves and stems, wet. I used it for several weekends during active growth, then a couple more times during the summer (which here is dry and sunny).

It's stinky (but in a garden fertilized with fish emulsion, we are used to that) the smell goes away in a day.

If yours is 100% neem oil, then my guess is to use it the same way (maybe just spray a few roses at first & see how they do).

This year I got excited and used it as a dormant spray as well, although I am not aware that it will work in that manner. (also, a month earlier I had used lime/sulfer on the same bushes)

At this point this year, the roses have about 4 inches of grown, some with buds. SO FAR (knock on rosewood), no blackspot or aphids (unfortunately I did not keep a garden calendar previously so I forget when these would appear). Again, there are signs of other insect life in the garden (lady bugs and spiders). If I do see aphids or black spot, I'll get out the neem and use as I did last yer.

I have not done a scientific experiment to see if the stuff works. But I do think that it does and obviously I am sold on it. WHether it works for you will depend on your roses, climate, and other factors, of course..

Hope this helps.

I use a product called Leaf Shine that was recommended by a rose specialist I buy my roses from. I have only just got on to this product and don't know yet what the benefits are. It's a natural product so I am happy to use it. So far I have had no problems but too early to report success. I will let you know next year what I think.
Anyone have any thoughts about Epsom salts, how to use it such as spray on the foilage or water through the roots on roses, rhodos and azaleas?
Zone 8 in rainy Abbotsford BC (dry in the summer)

Neem Oil products are broad spectrum poisons that will kill beneficial insects as well as your pests unless used with due diligence.
Whether Epsom Salts will be of any benefit or not depends on the condition of your soil. If you have a soil with low levels of Magnesium (Epsom Salts are Magnesium Sulfate) spraying some around might be of some help, but the only way to know that is to have a good, reliable soil test done. The Magnesium in Epsom Salts is very soluble and will not stay in your soil very long, but then again the amounts usually prescribed to use are so small that little is actually available to the plants.

I was greived to see my lovely fuzzy bumblebees killed by Neem, I watched them staggering around rose petals before dropping to the ground, dead. I had sprayed neem in good faith believing it to be an organic spray, that would not poison the environment. It should be labeled as an apicide, for that is what it is. Now I use Cornell spray, which must be applied more often, but is far safer. I use
1 and 1/2 tsp. of baking soda
1 quart water
1 tsp. canola oil.

This is 1/2 tsp. more baking soda, than the common recipe, and it does leave a powdery residue which works better in preventing the spread of p.m. and blackspot and rust. You can tell the white powder is not pm. because the leaf texture is not altered by the baking soda, unlike powdery mildew.
Luxrosa

I have a dreadful problem with these beetles called cetonie and June bugs;they chew up the flowers of roses like Japanese beetles do, but they come out in April, May and June, so they really damage the glorious spring flush. I got a large bottle of Neem oil and want to start a spraying program, to see if this will help me manage these awful pests somewhat.I read that you have to spray every 3 or 4 days, however,when the sun is low (very late in the day here in Tuscany, Italy). Does anyone have any comments or advice? thanks, bart

Neem oil is the best, but it has to be pure cold pressed to be effective. As far as foliage burn, you need to read the instructions and use it accordingly. If you live in a hot climate with lots of sun, only use in the evening. In regards to killing beneficial insects this is completely untrue, we have a healthy lady bug and bee population that are not bothered by it, if you use it mixed correctly.

I use Dyna-Gro Neem oil mixing it as instructed but instead of the mild soap it says to mix with it I use Dr. Bronners peppermint castile soap (same quantity). If you mix it use warm water and let the mixture sit overnight as neem oil is an oil and tends to not mix very well, especially if using cold water. Remix and enjoy natural cure

oh...I forgot to mention, we use it about every 2 weeks. I use it on my garden for pest control and various other plants for leaf blight.

Make sure you look at the ingredients, if its not 100% neem oil then dont expect similar results. I have heard all sorts of problems from blended mixtures or ones that use a chlorinated process to extract the neem oil...you want cold pressed neem oil 100%

I have never used neem oil before, but iam having so many problems with spider mites this season. I have 125 roses, and i used bayer 3 n 1 plus mite killer product, its a good product and i spray weekly but the mites still seem to be accumulating faster than i can spray, so iam hoping the neem oil along with the bayer will help. Has anyone use the neem oil for this purpose (mites)?

Hi,
I just want to say that my organic horticulturist told me that Neem ONLY kills beneficial insects if they are on the plant while you spray it. Today I was spraying my butterfly weed for a huge infestation of aphids (overly busy this week and did not get to do my every other daily walk through of our huge amount of gardens--I typically use insecticidal soap on aphids if they are on more than one spot on a plant, but not taking over the plant. If aphids are only on 1 or 2 tips of the foliage, I crush them with my fingers and then spray a jetstream of water on them--making sure it goes on the grass, not on the mulch or other plants). The aphids were thick on my plant today, and so I did a careful jostling of the plant, nearby plants, and ran my fingers through the mulch. Some spiders and a katydid left the scene quickly. I watched and waited to be sure they were long gone, rustled my plant again, and since there are no flowers, no bees were present. Good to go.

Again, Neem is poisonous to our garden friends only if they get sprayed. If they alight on the plant after it is sprayed, it will not harm them. The spray dries quickly, too. One last note. I do carry my little toad or tree frog friends to another part of the garden entirely before spraying ANYthing--even insecticidal spray! They are far too precious to lose.

Hi pjwgardener: Thank you for your organic ways, and caring for the beneficial creatures in the garden .. I feel the same way. I checked on Texas A&M link, it mentioned supplying calcium to plants to strengthen cell walls, so aphids can't nibble on. Below is a link with interesting info.:

"Natural Aphid Pesticides: Aluminum Foil
Place a square of aluminum foil around the base of plants affected by aphids. This causes light to bounce around to the underside of the leaves, which repels the aphids. It is also good for the plants, as it brings them more natural sunlight.

Natural Aphid Pesticides: Calcium Powder
Sprinkling calcium powder around the base of the plants is another natural aphid repellent. The aphids do not like the calcium and will generally stay away from it.

Natural Aphid Pesticides: Yellow Plastic Bowl
Aphids are naturally attracted to the color yellow. Place a yellow plastic bowl filled about 1/3 of the way with water in the center of the infested area. Many of the aphids will be drawn to the bowl and will go into the water and die.

Natural Aphid Pesticides: Banana Peels
Burying shredded banana peels around the base of plants is an odd, but effective remedy. It has been around for ages and many gardeners will swear by it.

Natural Aphid Pesticides: Smash Their Buddies
Squashing a few aphids near the infested area will signify to the other aphids that it is time to go. It's a chemical reaction.

Here is a link that might be useful: Natural Aphids Pesticides

Strawberryhill,
Calcium powder is something that I am not familiar with. A Google search shows many calcium supplements, some in powder form. How and where do you by yours ?
Don

Very useful information. I have never used neem oil but have been using raw neem leaves since I was a child, back in Pakistan. Rubbing neem leaves on neck, face and hands keeps one safe from insects, specially during hunting and fishing trips which I am very fond of. If one sits under a neem tree, there would hardly be any mosquito bite. Taking a bath with water boiled with neem leaves is excellent for all kind of skin diseases. Eating neem fruit (very bitter) is a time tested remedy against many diseases. But this all is use of fresh neem leaves / fruit. I have no idea about the characteristics of neem oil that you guys are talking about.

Has anyone tried boiling neem leaves in water and spraying it on affected plants? I have been doing that with good success and with no harmful effects to other wild life in the garden but no more as I haven't come across any neem tree in Canada.

regards

Hi Don: Thank you for an excellent question, I wonder the same. In rainy spring I had Gruss an Teplitz rose in the shade, it was infested with aphids despite the granular gypsum (calcium sulfate) in the pot.

Hi Khalid (RoserianPK): Thank you for that info. about Neem. That's very interesting! I appreciate your input both from your hot climate of Pakistan, and your recent relocation to Canada.

Later I found that gypsum from Menards doesn't dissolve, and gunk up after months. I have Sharifa Asma in partial shade, it's infested with aphid. I gave it soluble gypsum bought for $8 for 5 lbs. from Kelp4Less (free shipping) ... Instant result: thicker stems and leaves, and no more aphids.

Gypsum contains 17% sulfur, great for my pH 8 tap water and pH 7.7 clay, but not good for those with acidic soil and neutral tap water. As the pH drops, less potassium and calcium available for plants.

I accidentally induced aphids on Christopher Marlowe when I gave it too much sulfur, leaves became thinner, stems became less rigid, and more succulent for aphids to chew.

Calcium chloride is used in canning to firm up fruits and vegetables. Calcium chloride is documented in agriculture for better root growth. It's higher in salt than gypsum (salt index of 8), but calcium chloride is fast-acting. There are better forms of calcium, depending on your soil /climate /tap water:

Gypsum provides 22% calcium, 17% sulfur, with salt index of 8.1, used to de-salt sodic soil, also to neutralize bicarbonates in alkaline tap water.

Dolomitic Limestone provides 25% calcium and 10% magnesium, salt index 0.8, sandy soil lacks magnesium

Calcitic limestone provides 36% calcium when the rain water (pH 5.6) breaks it down, low salt index 4.7

Colloidal rock phosphate provides 19% calcium and 18% phosphate. Best for acidic soil, cannot be utilized at pH over 7.

Hard rock phosphate provides 48% calcium and 30% phosphate, cannot be utilized at pH over 7.

From EarthCo. soil testing company booklet: Steamed bone meal has 11% phosphorus and 24% calcium. Bone meal cannot be utilized if the pH is over 7.

Superphosphate provides 20% calcium, 12% sulfur, and 20% phosphorus, low salt index 7.8

Wood ashes provides 20% calcium, 2% phosphorus, 7% potassium, magnesium, and all trace elements. CAUTION: Wood ash is very alkaline, pH over 10, will burn roots if applied directly to plants.

Below is an excellent research by Texas Agricultural Extension, documenting how SOLUBLE calcium increases ammonium, phosphorus, potassium absorption, and stimulates photosynthesis and plant growth.

Here is a link that might be useful: Using soluble calcium to stimulate plant growth

This post was edited by Strawberryhill on Sun, Sep 8, 13 at 13:06

2 ounces to 1 gallon water