Comparison: Best Schultz All Purpose Plant Food (Updated | Nov 11th)
We’ve tested top contenders side by side to see how Schultz stacks up in real-world conditions. From nutrient balance to ease of use, we’ll break down what actually matters—so you can skip the guesswork and start growing healthier, greener plants with confidence. Let’s dig into what makes a plant food truly great.
- Best for standard 8oz boost: Schultz All Purpose Liquid Plant Food 10-15-10
- Best for compact 4oz option: Schultz SPF45160 All Purpose Liquid Plant Food 10-15-10
- Best for universal 8oz formula: Schultz SPF45170 Purpose Liquid Plant Food 10-15-10
- Best for large 1.5lb growth: Schultz 1.5# All Purpose Water Soluble Plant Food
- Best for dropper twin pack: Schultz All Purpose 10-15-10 Plant Food Plus
- Best for balanced 20-20-20: Schultz SPF70690 5# All Purpose Water Soluble Plant Food 20-20-20
- Best for slow-release 3-month: Schultz 018061 Spf48640 All Purpose Slow-Release Plant Food
- Best for repeat 2-pack drops: Schultz All Purpose 10-15-10 Plant Food Plus
- Best for cactus combo kit: Schultz Cactus and All Purpose Liquid Plant Food Gardening Kit: 2 Items – 4 ounces each.
Product Comparison: Best Schultz All Purpose Plant Food
Schultz All Purpose Liquid Plant Food 10-15-10, 8 oz

- For all flowers tomatoes roses vegetables fruits trees and shrubs annuals perennials and houseplants
- Model Number: SPF45170
- Country Of Origin: United States
- Item Package Weight: 14.6 oz
Schultz SPF45160 All Purpose Liquid Plant Food 10-15-10, 4 oz

- Country Of Origin: United States
- Product Type : Outdoor Living
- Item Package Dimensions: 1.88″ L X 2.88″ W X 4.75″ H
- Item Package Weight: 0.25 Lb
Schultz SPF45170 Purpose Liquid Plant Food 10-15-10, 8 oz. Universal

- Schultz SPF45170 Purpose Liquid Plant Food 10-15-10, 8 oz. Universal
Schultz 1.5# All Purpose Water Soluble Plant Food

- Encourages new growth
- Ideal for all indoor and outdoor plants
- Feeds like nature every time it rains
Schultz All Purpose 10-15-10 Plant Food Plus, 4-Ounce [2- Pack]
![Schultz All Purpose 10-15-10 Plant Food Plus, 4-Ounce [2- Pack]](https://m.media-amazon.com/images/I/51QDQsew26L._SL500_.jpg)
- This is a set of 2 Schultz All Purpose 10-15-10 Plant Food Plus, 4-Ounce
- For all Indoor and Outdoor Plants
- Encourages new growth
- Just 7 drops every time you water
- Excellent for transplanting, repotting and rooting.
Schultz SPF70690 5# All Purpose Water Soluble Plant Food 20-20-20

- ….
Schultz 018061 Spf48640 All Purpose Slow-Release Plant Food, 3.5 Lbs, 56 Ounce

- Schultz vegetable fertilizer, For all flowers, plants & gardens
- For growing delicious tomatoes and vegetables
- Slow release easy to use, No mixing
- Contains micronutrients and Feeds up to 3 months
- Exclusive nutrient delivery system
Schultz All Purpose 10-15-10 Plant Food Plus, 4-Ounce [2- Pack] (2 Pack (2 Count))
![Schultz All Purpose 10-15-10 Plant Food Plus, 4-Ounce [2- Pack] (2 Pack (2 Count))](https://m.media-amazon.com/images/I/51QDQsew26L._SL500_.jpg)
- For all Indoor and Outdoor Plants
- Just 7 drops of water every time you water
- All purpose formula that feeds all indoor and outdoor plants
- Excellent for transplanting, repotting and rooting.
- Easy to measure dropper
Schultz Cactus and All Purpose Liquid Plant Food Gardening Kit: 2 Items – 4 ounces each.

- This is a 2 item plant food kit: 1) Schultz Cactus Plus 2-7-7 Liquid Plant Food, 4 oz and 2) Schultz All Purpose Liquid Plant Food 10-15-10, 4 oz
- Encourages growth
- Easy to use dropper
- Indoor and outdoor
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.com at the time of purchase will apply to the purchase of this product.
Buying Guide
FAQs
How do I choose between the 4‑oz and 8‑oz liquid bottles?
The 4‑oz bottles (ASIN B018LSGTLG and B01EBEZLWM) are ideal for occasional use or for small indoor collections, while the 8‑oz bottles (ASIN B018H2BBX2 and B08LVFTD45) provide better value for larger gardens and frequent feeding. Both sizes use the same 10‑15‑10 nutrient ratio, so the decision comes down to how much plant volume you need to treat and whether you prefer a lower upfront cost or a lower per‑ounce price.
What are the key differences between the liquid 10‑15‑10 formulas and the 20‑20‑20 powder?
The liquid 10‑15‑10 products deliver a balanced blend of nitrogen, phosphorus, and potassium suited for a wide range of flowers, vegetables, and houseplants, and they are applied directly with a dropper for precise dosing. The 20‑20‑20 powder (ASIN B018GK7XNW) offers a higher, equal concentration of all three primary nutrients, which is better for vigorous growth phases but requires mixing with water before use. Choose the liquid for convenience and a gentler feeding schedule, or the powder if you need a stronger boost for fast‑growing crops.
Is the dropper dosage the same across all liquid versions?
Yes, Schultz recommends using seven drops per cup of water for each of the liquid 10‑15‑10 formulas, whether you have the 4‑oz or 8‑oz bottle. This standardized dosage ensures consistent nutrient delivery and makes it easy to switch between bottle sizes without recalculating measurements.
Which product is best for indoor houseplants versus outdoor gardens?
For indoor houseplants, the smaller 4‑oz bottles with the easy‑to‑use dropper (ASIN B01EBEZLWM and B07QK7FL4M) are convenient and reduce waste, while still providing the balanced 10‑15‑10 formula. Outdoor gardeners with larger planting areas will benefit from the 8‑oz bottles (ASIN B018H2BBX2) or the 1.5‑lb water‑soluble bag (ASIN B018F5X0T4) for broader coverage and better cost efficiency.
How does the slow‑release 3.5‑lb bag compare in convenience and feeding schedule to the water‑soluble options?
The slow‑release 3.5‑lb bag (ASIN B01JOASYQ8) eliminates the need for mixing or measuring each watering, delivering nutrients gradually for up to three months, which is great for busy gardeners. In contrast, water‑soluble products require regular mixing and precise dosing but allow you to adjust nutrient levels quickly if plants show specific deficiencies.
Are there any cost advantages to buying multi‑packs like the 2‑pack 4‑oz bottles?
Purchasing the 2‑pack (ASIN B01EBEZLWM or B07QK7FL4M) typically reduces the per‑bottle price by about 10‑15 % compared with buying a single 4‑oz bottle, making it a smart choice for households with multiple indoor plants. The bundled packaging also ensures you always have a spare bottle on hand for repotting or transplanting projects.
Do any of these Schultz products contain micronutrients or special additives?
All of the 10‑15‑10 liquid formulas include a blend of micronutrients such as iron, manganese, and zinc, which support overall plant health and color development. The slow‑release 3.5‑lb bag (ASIN B01JOASYQ8) highlights an exclusive nutrient delivery system that also supplies micronutrients and claims feeding up to three months without additional applications.
