Osmocote® Product FAQs

Find answers to your Osmocote® questions by clicking on an item below.

How to use Osmocote® plant food

Osmocote is available in two formulations:

Outdoor & Indoor Plus (Analysis 15-9-12 with minors)

  • Ideal for pots, window boxes, hanging baskets, anything in a container
  • Annuals
  • Indoor plants
  • Plants in raised beds

Flower & Vegetable (Analysis 14-14-14)

  • Tomatoes, garden vegetables, melons, berries
  • Perennials
  • Trees and shrubs
  • Most anything in mother Earth
Yes. In fact, Osmocote® Flower & Vegetable Plant Food is formulated for just these purposes. Each granule contains essential plant nutrients such as nitrogen, phosphorous and potassium. Nutrition is released into the soil slowly so that plants have a ready supply as they grow. Osmocote® granules are coated with a resin made from vegetable oil, which make them safe to handle with bare skin. Of course, it is always wise to wash hands following exposure to any garden product and it is also best to avoid ingesting granules directly or touching eyes after granules are handled.

Osmocote® is not recommended for cut flowers. It is a slow release product that works with the plants root system. The life of cut flowers can be extended, however, by a combination of the following actions:

  1. clean the container daily but do not use soap or detergent,
  2. re-cut the stems (they may become clogged),
  3. replace the water with fresh,
  4. store cut flowers in a cool place during the night,
  5. display cut flowers away from heat during the day (that is, avoid windows, TV’s and other electronic devices, radiators, kitchen stove, etc.).

Yes. Osmocote® can be used on all varieties of potted plants. Apply as directed for best results.

Click to see the application instructions for each formula:

Osmocote® Outdoor & Indoor Plus should be applied every 6 months. Osmocote Flower & Vegetable® should be applied every 4 months.

It’s important that Osmocote® be applied dry. Do not pre-mix the product with water before applying. Further, it’s not necessary to water plants immediately after Osmocote® is added in order to reduce the potential for chemical “burn.” Osmocote® has a resin coating that encapsulates the nutrients. Direct contact by the product with plants is not a problem.
One of the nice features of Osmocote® is that it can be applied just about any time. Early spring is always a good time to start the feeding process as long as the ground is not frozen.

It’s best to work product into the top 1-3 inches of soil or mulch, but even when that’s not possible, the melting of late snow and/or early spring rains will work the granules into the soil. As ambient temperatures begin to climb, so, too, will soil temperatures. The release of nutrients from the Osmocote granules will track the steady rise in soil temperatures thus ensuring that the right amount of nutrition is available when plants are able to use it.

The ideal soil temperature for plants is between 50ºF – 70ºF which coincides with the release of Osmocote nutrition. When feeding annuals, it’s best to apply in-the-hole as plants are transferred from flats to pots or mother Earth. A second feeding may be appropriate four months later. Fall is also a good to time to feed perennials

Applying Osmocote® Plant Food

It’s as simple as spreading the recommended amount and mixing into the soil. Please refer to the FAQs for more information.

Tell me about Osmocote® plant food

Osmocote® is a manufactured product — meaning, essential plant nutrients are formed into individual granules then encapsulated so that nutritional release can be controlled to fit the pattern of nutrient uptake in the plant that it feeds.

Because excessive nutrition is not released into the soil, the environment benefits in two ways:

1) plants will not be overfed (that is, “burned”) and 2) overwatering or heavy rainfall will limit washing away of nutrients into streams and lakes.

Osmocote® granules can last for as much as eight (8) years when stored properly. Proper storage means being in a relatively cool but dry place. If granules get wet (either from water or high humidity) or high temperatures, they may begin to release some of their nutrients and the remaining product may become less effective when it is finally applied.
Compared to the top selling brand of slow-release plant food, Osmocote® contains almost 2X the amount of slow-release nitrogen per pound of product.

Osmocote® granules are nearly perfect spheres and uniform in size. This ensures that nutrient release works the same way with each granule and contributes to the consistency of the nutrient release.
Osmocote® has a resin coating, a characteristic that’s somewhat elastic. This reduces the risk of the granules cracking and inadvertently releasing nutrients during the packaging process or when the product is in transit to the retail store.

Click here to see the analysis of the Osmocote® products!

Osmocote® for consumers and Osmocote® for professional growers utilize the same technology. Both products use the same prills (granules) and the same unique resin coating. In fact, these products are manufactured in the same plant in Charleston, South Carolina.

While the consumer product is available in just two formulas, the professional product is produced in nearly 50 formulas because professionals require a broader range of NPK analyses depending upon the crop they are growing and local growing conditions.

Osmocote® for consumers is available in four sizes, 1-lbs and 2-lb. bottles (O&I and F&V), 4.5-lb. shaker bottle (F&V) and 8-lb. bags (O&I and F&V). Osmocote® for professionals is packaged in 50-lb. sacks.

No, which is the point of a slow-release plant food. Instead, Osmocote® nutrients are released into the soil as replacements for the nutrients being drawn into the plant’s root system.

The temperature of the soil controls the rate at which nutrients are taken up by the plant and the rate at which nutrients are released by the Osmocote® granules. The warmer the soil, the faster nutrients are released. Conversely, when soil temperatures drop, so does the release of nutrients.

Professional growers frequently use a water-soluble fertilizer in addition to Osmocote®. Water-soluble fertilizer is absorbed partially through the leaves (foliar feeding). This compliments the root-feeding properties of Osmocote®.

When using a water-soluble product with Osmocote, be sure to follow the recommended rate on its package but then cut that amount by half. Typically, a water-soluble fertilizer has a roughly two-week impact on the plant, but meanwhile, Osmocote continues goes right on feeding for up to four (4) months!

No, Osmocote® does not contain staining agents.
The product should be stored in a cool, dry place. When the product is exposed to moisture or high temperatures, nutrient release could begin making the product less effective when eventually applied.
Osmocote® is not harmful to animals when used as directed.
Sometimes the spent shells are mistaken for product that failed to activate and release nutrients. These shells are actually empty and are residual material. After osmosis occurs and all of the nutrients are released, the remaining granule is empty. These shells will eventually disintegrate into the soil.
Because of its unique resin coating, Osmocote® does not have an offensive odor.
The ingredients in this product are as natural as the first 92 elements in the periodic table. A plant does not distinguish between nitrogen from chicken manure versus nitrogen from natural gas. Nitrogen is nitrogen. Nitrogen from Osmocote® has limited leeching, even after it is exposed to heavy rainfall or overwatering.

There is no problem in reconciling the desire to protect the planet and the use of a product that uses nutrients that are already part of the core universe and are measured in their application.

All About Osmocote® Plant Food

Osmocote granules are nearly perfect spheres and uniform in size to ensure consistent release. Please refer to the FAQs for more information.

How to purchase Osmocote®

Osmocote® is a good value. What consumers are buying is slow-release nitrogen. The amount of slow-release nitrogen is critical to plant food performance (it almost always drives plant growth). On a price per pound for slow-release nitrogen basis, Osmocote® is competitively priced. In other words, you get what you pay for!

Where to Buy?

Click to find Osmocote® Products online or in a store near you.

“Here’s the product information you’ll want to know”

Sign up for the PlanterPlace newsletter

If you love to garden, you need the newsletter! When you sign up, you’ll get our exclusive newsletter, bursting with gardening articles, videos, and tips.

Sign Up Now