Scotts Super Bloom Water Soluble Plant Food, 2 lb - NPK 12-5

The Verdict

Let’s be direct: most bloom boosters are overpriced snake oil with a pretty label. The Scotts Super Bloom Water Soluble Plant Food is not that. This is a straightforward, high-phosphorus feed that does exactly what it claims — and at a price point that won’t make you wince.

What’s actually in the bag

You’re getting 2 pounds of fine, blue-green crystalline powder. The NPK ratio reads 12-5-5 — that’s 12% nitrogen, 5% phosphorus, and 5% potassium. The phosphorus is the star here. It’s the nutrient responsible for flower initiation, fruit set, and root development. The nitrogen is kept relatively low to prevent the plant from channeling energy into foliage instead of blooms.

The included scoop is a small plastic measuring spoon — roughly one tablespoon. One level scoop mixes into one gallon of water. The 2-pound bag yields approximately 200 gallons of mixed solution. For context, that’s enough for 20 weekly feedings for a typical 10-plant container garden.

How it performs in the real world

I’ll cut to the chase: this stuff works fastest on plants already in a growth cycle. Roses, geraniums, petunias, and tomatoes respond within 7-10 days. You’ll see buds set sooner, and established blooms hold their color longer. The water-soluble formula means nutrients are immediately available — no waiting for soil microbes to break anything down.

One Amazon reviewer put it plainly: “I’ve used this on my hanging baskets and container tomatoes all summer. The difference between plants fed with this versus my regular all-purpose fertilizer is night and day — twice the flowers, and the tomatoes set fruit about a week earlier.”

Another buyer mentioned using it on their hibiscus: “Three weeks after switching to Super Bloom, my hibiscus went from one or two blooms a week to five or six. It’s now my go-to for anything I want to flower.”

Where it falls short

The 12-5-5 formula is potent. If you’re growing seedlings, young transplants, or fussy plants like orchids, this will burn them. You’ll need to cut the concentration to half-strength or quarter-strength. The label doesn’t mention this — I’m telling you because I’ve seen the crispy leaf edges.

Also, this isn’t a set-it-and-forget-it product. Because it’s water-soluble, it leaches out of soil quickly, especially in containers with frequent watering. You’re committing to a weekly or bi-weekly feeding schedule. If you forget for two weeks, blooms will taper off noticeably.

Who should buy this

This is for the gardener who wants visible results without paying boutique fertilizer prices. It’s ideal for:

• Container gardeners growing flowering annuals or vegetables — the quick-release formula matches the frequent watering containers demand
• Rose enthusiasts looking for a supplemental bloom feed alongside their regular maintenance program
• Tomato and pepper growers who want to push fruit set mid-season
• Budget-conscious gardeners who want a proven formula from a major brand without the specialty-store markup

Skip it if you’re growing mostly foliage plants, starting seeds, or prefer organic amendments. This is a synthetic, salt-based fertilizer — effective, but not what you want for an organic regimen.

FAQ

Q: Can I use this on indoor houseplants? Yes, but dilute it to half strength. Indoor plants grow slower and need less food. Use it on flowering houseplants like African violets or peace lilies, but skip it for foliage-only plants like pothos or snake plants.

Q: How often should I apply it? Every 7-14 days during the active growing season. If you’re using it on container plants that get watered daily, lean toward the 7-day mark. In-ground garden beds can stretch to 14 days.

Q: Will this work on my lawn? No. This is formulated for flowers, vegetables, and ornamental plants. For lawns, you want a higher nitrogen formula. Using Super Bloom on grass will produce weak, underfed turf.

The Verdict

Buy it if: You want bigger, more abundant blooms on flowering plants and vegetables, and you’re willing to stick to a weekly feeding schedule.

Skip it if: You’re growing seedlings, prefer organic fertilizers, or want a slow-release option that doesn’t require regular reapplications.

At 4.6 stars from 229 ratings, Scotts Super Bloom delivers consistent results at a fair price. It’s not fancy, but it works — and in the world of garden fertilizers, that’s what matters.

Rating: 4.6/5

Where to Buy

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Last updated: 2026-08-06. Ratings and prices current as of review date. Verify on Amazon before purchasing.