What Is A 17-0-5 Fertilizer Blend (NPK Turf Blend)
A 17-0-5 fertilizer is a turf product whose guaranteed analysis lists 17% nitrogen, 0% available phosphate, and 5% soluble potash by weight. It supplies nitrogen for turf growth and potassium, but no guaranteed available phosphate. The right application rate depends on your lawn’s needs and the product label, not the numbers alone.
Fertilizer numbers can look like a code when you first see them on a bag or in a lawn-care guide. The basic idea is timeless: the three numbers describe the amounts of key plant nutrients, while the label tells you how to use that particular product safely. I’ll break down both so you can judge what a 17-0-5 blend does and how to read its rate.
What does 17-0-5 mean?
A 17-0-5 fertilizer contains, by product weight, 17% total nitrogen (N), 0% available phosphate (P₂O₅), and 5% soluble potash (K₂O). These are the guaranteed-analysis values, not a recommendation for how much fertilizer to apply. The label provides product-specific details, including directions and any other declared ingredients.
How to read the NPK numbers
NPK is shorthand for nitrogen, phosphate, and potash as listed on a fertilizer label. The second and third numbers are expressed as P₂O₅ and K₂O, not as elemental phosphorus and potassium. For practical lawn calculations, use the guaranteed-analysis numbers and follow the product label.
For every 100 pounds of this blend, the analysis guarantees:
- 17 pounds of total nitrogen
- 0 pounds of available phosphate (P₂O₅)
- 5 pounds of soluble potash (K₂O)
The zero means the product guarantees no available phosphate. It does not tell you what the lawn needs, and it is not a reason to skip soil testing where that is appropriate. A product’s ingredients, nitrogen sources, and controlled-release portion cannot be identified from “17-0-5” alone. Check the specific label for those details.
What is a 17-0-5 turf blend used for?
This blend can provide nitrogen and potassium to turf when those nutrients fit the lawn’s needs. Because its guaranteed available phosphate is zero, it is not a source of that nutrient according to the analysis. Whether it is suitable depends on the grass, season, soil information, local rules, and product directions.
Nitrogen supports turf growth and color, while potassium is an essential plant nutrient. But a higher nutrient number does not automatically mean better results. Applying extra nitrogen to chase color can injure turf and increase the chance of nutrient runoff. A soil test, where suitable, can help inform whether phosphorus or potassium is needed; local fertilizer rules may also limit what you can apply.
| Lawn situation | What the 17-0-5 analysis tells you | What to check next |
|---|---|---|
| You want to supply nitrogen | The product contains 17% total nitrogen by weight | Label rate, lawn area, turf type, and timing |
| You need a product with no guaranteed phosphate | The analysis lists 0% available phosphate | Local regulations and soil-test guidance |
| You want to add potassium | The product contains 5% soluble potash by weight | Whether potassium is appropriate for your turf |
| You want to know if nitrogen releases slowly | The three numbers do not show release type or proportion | The product label and any listed nitrogen-source details |
A 17-0-5 blend is not a complete answer to every lawn problem. Poor color can have causes other than low nitrogen, and this analysis does not reveal all product properties. Start with the lawn’s actual needs, then match them to the full label.
How do you calculate the application rate?
Calculate product needed by dividing your desired nitrogen rate by 0.17, the nitrogen fraction in a 17-0-5 blend. The desired nitrogen rate must come from appropriate guidance and the product label; the calculation only converts that rate into an amount of product. It is not a universal lawn recommendation.
Product rate = desired nitrogen rate ÷ 0.17
For example, if a label and your lawn plan call for 0.5 pound of nitrogen per 1,000 square feet:
- 0.5 ÷ 0.17 = about 2.94 pounds of product per 1,000 square feet.
- That amount supplies about 0.147 pound of K₂O per 1,000 square feet.
- Since 1 acre is 43,560 square feet, the same rate is about 128 pounds of product per acre.
These figures are examples of arithmetic, not recommended rates for every lawn. Set your actual nitrogen rate and timing using the product label, turf species, season, soil information, and applicable local fertilizer rules. Do not apply more to compensate for weak color or uneven growth.
How should you prepare before applying it?
Preparation means checking whether the product suits the turf, reading its directions, measuring the treatment area, and planning safe handling. Before opening the bag, review the full label and safety data. Those sources provide product-specific directions, including approved spreader type, rate, protective equipment, and any watering instructions.
Measure the lawn area you intend to treat and calculate the amount of product needed. Keep people and pets away while you work, protect nearby drains and water, and wear any personal protective equipment (PPE) the label specifies. Do not assume that settings or directions from another fertilizer apply to this one.
If the label does not support use on your turf or with your spreader, do not proceed on guesswork. Confirm the directions first. This small check can prevent a misapplication and help keep fertilizer out of places it does not belong.
How do you calibrate and apply a 17-0-5 blend?
Calibration checks how much product your spreader releases over a known area. Use the label’s spreader settings as a starting point, then calibrate on a measured area according to the product directions. Apply only the calculated amount, distribute it as directed, and stop if the spreader spills or appears to release product unevenly.
- Set up the spreader. Use only a spreader type and settings approved by the product label.
- Measure a test area. Follow label directions to check product output over a known area; do not estimate by eye.
- Load the calculated amount. Avoid filling or dispensing more product than the planned area requires.
- Apply in the specified pattern. Follow the label’s instructions for spread pattern and overlap to promote even coverage.
- Keep granules on turf. Avoid pavement, drains, and water. If granules land on a hard surface, sweep them back onto the intended turf area when safe and label-compliant.
Do not apply if calibration seems wrong or product is spilling. Uneven distribution or overapplication can cause fertilizer burn, meaning turf injury from excessive fertilizer in an area. Extra nitrogen can also increase runoff risk. Follow the label’s spill and first-aid directions if a spill occurs, and keep granules out of drains and waterways.
Worked examples: converting a lawn plan into product
These examples show how the same calculation changes with the planned nitrogen rate and lawn area. They are arithmetic scenarios, not field case studies or recommendations. Use a rate only when it is appropriate for your turf and allowed by the specific product label and local rules.
| Example plan | Calculation | Product amount |
|---|---|---|
| 0.5 lb N per 1,000 sq ft | 0.5 ÷ 0.17 | About 2.94 lb per 1,000 sq ft |
| 1,000 sq ft at that example rate | 2.94 × 1 | About 2.94 lb total |
| 5,000 sq ft at that example rate | 2.94 × 5 | About 14.7 lb total |
| 1 acre at that example rate | 2.94 × 43.56 | About 128 lb total |
The useful check is to compare the planned total with the area you measured. If the amount needed seems inconsistent with the package directions, pause and recheck the area, rate, and units before spreading.
What should you do after application?
After application, follow the label for watering and cleanup, then secure the product and equipment. Do not water in automatically: water only if the label directs it. Clean any granules from hard surfaces, close and clean the spreader as directed, and wash your hands and exposed skin.
Store fertilizer dry in its original sealed container, secured away from children, pets, and food. Follow label instructions for handling and storage. Keeping the product in its original packaging also helps preserve the directions and safety information you may need later.
For seasonal planning, use the label and relevant turf or soil guidance to set timing and rate. The NPK numbers do not tell you when to fertilize, how often to apply, or whether a specific lawn needs this blend.
Key takeaway
A 17-0-5 blend supplies 17% nitrogen and 5% soluble potash by weight, with 0% guaranteed available phosphate. The numbers describe nutrient content, not a universal application rate. Check the full label, calculate from an appropriate nitrogen rate, calibrate the approved spreader, and keep granules away from drains and water.
Frequently asked questions
These answers clarify what the analysis can tell you and what it cannot. For actual rates, handling directions, and timing, use the label on your specific product and follow applicable local fertilizer rules.
Does 17-0-5 contain phosphorus?
The guaranteed analysis lists 0% available phosphate (P₂O₅), so it does not guarantee available phosphate as a nutrient. That number alone does not tell you what your lawn needs. Use appropriate soil guidance and check local rules before choosing a fertilizer.
What does the 17 mean in 17-0-5?
The 17 means that the product contains 17% total nitrogen by weight. In 100 pounds of product, that equals 17 pounds of nitrogen. It does not state the nitrogen source or how quickly nitrogen becomes available; check the full label for those details.
What does the 5 mean in 17-0-5?
The 5 means the product contains 5% soluble potash (K₂O) by weight. That equals 5 pounds of K₂O in 100 pounds of product. The analysis does not show whether your lawn needs potassium, so consider relevant soil guidance and label directions.
How much 17-0-5 should I apply per 1,000 square feet?
There is no single rate for every lawn. Divide the nitrogen rate that is appropriate for your turf and allowed by the label by 0.17. For example, 0.5 pound of nitrogen requires about 2.94 pounds of product per 1,000 square feet.
Can I use 17-0-5 on any type of grass?
Do not assume it suits every grass or situation. Check the product label for approved turf uses and directions, then consider turf species, season, soil information, and local fertilizer rules. If the label does not support your intended use, do not apply it.
Does the 17-0-5 number show if nitrogen is slow-release?
No. The NPK analysis gives nutrient percentages, but it does not identify the nitrogen sources or controlled-release fraction. Review the specific label for that information. Do not infer release speed from the 17-0-5 numbers alone.
Should I water after applying 17-0-5?
Water only if the product label directs you to do so. Watering instructions can vary by product, so a general rule is not a substitute for the label. Check those directions before application and follow them for the specific blend.
What if I spill or overapply the fertilizer?
Stop the application and follow the label’s spill and first-aid directions. Prevent granules from reaching drains or water. Overapplication or uneven coverage can injure turf and raise runoff risk; do not add more product to compensate for poor color or coverage.
(This article was written by one of our staff writers, Evan Bradley. Visit our Meet the Team page.)
