BonideCaptain Jack's Copper Fungicide, 32 oz Ready-to-Use Spray for Organic Gardening, Controls Common Diseases

I bought this to control rose rust on June 3rd, 2025. Today is July 2nd, 2025 and the rose bushes that seemed lost to fungus have exploded with new growth and all have lots of new leaves, a few new stems, and at least one new bud, depending on the variety. The tea roses that were in okay shape almost need to be trimmed back, they've grown so much. This is despite numerous rainy days washing off the product. I intend to try this on my pear tree next; if it works, I'll update the review. Highly recommend this for rose rust, though I can't yet speak for anything else.

My peony leaves developed brown spots/ blotches over the past few years. Since it really detracted from the beauty of the plant, I researched on Google how to get rid of it and this was recommended. I followed the bottle instructing and I had zero brown blotches this year! It worked beautifully! My plants were absolutely gorgeous this year. Would buy again, and will.

I had a persistent red fungus attacking the leaves on my peach tree. It was aggressive and spreading fast. I used this product as directed and also pulled off the affected leaves. While I still saw some fungus after the first application, it was definitely reduced.Here’s the twist: This year, there’s zero sign of the red fungus, and my tree is bigger and healthier than ever. Did Captain Jack’s do the trick? Maybe! I can’t say for sure if it was the spray, the winter, or a mix of both, but I do believe this fungicide played a part in getting my tree back on track.It may not work overnight, but if you're consistent and patient, this product seems to help. A solid addition to your garden toolkit, especially if you're battling stubborn leaf issues.The smell is non-toxic. The bottle spray worked well. My peach tree is now two years old, so it's still relatively small. This bottle was more than enough for my one tree and many uses.

My endless summer hydrangea was in bad condition of black-spot-leaves, and chatgpt said it was anthracnose. I trimmed off the infected leaves, but even the new growth came out sick. I bought this item out of desperation and it did work! Now I keep spraying once a week, and the new leaves came out healthy and strong. It’s like magic in a bottle!

Background: New England Zone 6a/6b (big snow, ice, and frigid winters), first attempt at growing citrus in container pot. I know, who up here even tries! Gourmet chef (or sad Wannabe) whom cultivates my own herbs for my dishes year-round.Subject: ~ 2’ tall Meyer lemon tree in container pot.Situation: Never used a fungicide before, but total success with Captain Jack’s de-bug product. For those new to the line, I can’t emphasize enough how important it is to read their products’ comprehensive brochures from beginning to end before using. I bought this copper fungicide product to help me combat what I suspect was early powdery mildew on my baby Meyer lemon tree. The tree is my very first citrus, in a container I immediately transpotted with bottom pebbles, Coast of Maine organic worm-casting potting soil, lots of perlite for better drainage and to monitor its roots through the clear plastic. Success! It was thriving all summer outside, and even exploded in new blooms and put out about 15 baby lemons, most of which dropped (because Meyers sacrifice when it senses its young stems can’t support). Then I brought it indoors to winter, still fruiting with three green globes, and placed it under one of my grow lights in a heated low humidity room.What baffled me was, despite my attention to the amount of natural light, temperatures, and minimal water it demanded, it was suddenly showing signs of mildew. To my surprise, the fungicide’s brochure explained how powdery mildew is unique and doesn’t require any water to take hold. It made sense.Remedy: I’ve cared for all of my indoor plants either where they are or in my kitchen sink. But being I’m so fond of this little lemon tree, it’s got thorns to kill, and I mean business, this one wasn’t going to be just a sink job. Armed with the Captain Jack’s fungicide, I first removed and pitched the topmost crust of soil and anything dead or remotely white, then sprayed-turnedover-sprayed the first few inched of soil, lower stems, and lower leaves in the sink. Then when dry, I moved it to the tub, massaged the top two inches of soil with more spray, and retreated the tops and underside of every leaf. I let it air dry. The most egregious white spots reappeared as it dried, but I resisted the temptation to spray it again, knowing the fungicide just takes time to work. I returned it to its place under its grow light (a Soltec canister beam).One week later, the Meyer Lemon’s leaves, while not out-of-the-woods, are showing signs of stability, if not improvement. New buds have emerged at many stem’s ends, and its spikes have grown and hardened, as if to protect its remaining nascent fruit. The fruit is looking good. 🍋Another week later, the tree is looking great, with only a few tiny stubborn (or resistant) patches of powdery mildew (?) remaining. The 3 fruits look great, and all but one of the many new buds are growing. It’s lost no leaves since last week, and definitely thriving. I reapplied the fungicide spray again to the fruit, leaves, and soil. Conclusion, Captain Jack’s Copper Fungicide saved my Meyer Lemon.

I haven’t used the product because the sprayer was broken when I tried to use it. I went to spray and the tip and cylinder plastic piece fell on ground.

I always keep this product in stock so I can immediately treat my plants when they get powdery mildew or other mold on their soil. It might take a few treatments, but it takes almost no time, and hasn't failed me yet.

Have been using for years and works pretty well. There is a little bit of an order while spraying, but once dried is odorless.