Using Sea Kelp in the Garden

Aquatic plants give organic gardens an unexpected boost.
Kelp improves a plant’s ability to take in nutrients.

Using Kelp in Soil

Using kelp as a soil amendment helps plants grow stronger and healthier by improving their ability to take in nutrients.

Photo by: Image courtesy of Organics Rx.

Image courtesy of Organics Rx.

Using kelp as a soil amendment helps plants grow stronger and healthier by improving their ability to take in nutrients.

Seaweed isn’t necessarily the first thing that leaps to mind when it comes to plant care, but that may be changing. A marine algae found growing in shallow ocean waters, kelp is not a new idea in gardening.  Although the practice of using kelp to promote nutritional intake in plants has been around for decades, an increased interest in gardening without the use of synthetic products has brought kelp back into the spotlight. Unlike many amendments, kelp helps plants make the most of what already exists in the soil and the effects can be dramatic.

Tom Schreiber, CEO of OrganicsRx, a manufacturer of organic plant foods, gives us the lowdown on the organic powerhouse and explains what it can do for plants both indoors and out.

“Kelp has a lot of micronutrients,” says Schreiber, “but it also helps to open up root systems in plants to better take in the nutrients in the soil. It’s kind of like drinking from a coffee stir and then switching to a straw.  Taking in more nutrition means stronger, healthier plants.”

The restorative effects of kelp on plants is largely due to high levels of cytokinin, a natural growth hormone that promotes cell division in plants, resulting in root and shoot growth, improved photosynthesis overall improvement in plant health.  Kelp is also a powerful bio activator, which helps break down compost and plant material, improving soil conditions. Schreiber says plants of all kinds can benefit.

“Kelp can be used in a lot of ways. It can be spread on lawns in the summer to help beat the heat. It can be used in vegetable gardens, container gardens or on houseplants. It can be added to soil at the time of planting to give the roots an easier time during transplanting or used to help already established plants,” continues Schreiber. “If you have a plant that’s stressed and not doing well, (adding kelp to the soil) is almost like a vitamin shot and plants will perk right back up.”

“Organic gardening is something people want to get behind, but you need to be able to find clean, natural ways to encourage comparable or superior plant growth to what’s found with synthetic products. Kelp is an equalizer. It allows organic methods to work at a level that’s more consistent with synthetics.” For organic gardeners, Schreiber says kelp will help give them a leg up.

“It’s a clean, green and effective. Organic gardening is difficult, but kelp can make a substantial difference,“ concludes Schreiber. “Kelp makes it easy to go organic without feeling like it’s a sacrifice.”

Next Up

How to Install Garden Lights

Whether you're after that cozy glowing garden look or you simply need to safely traverse your garden after nightfall, here are simple steps for installing garden lighting.

30 Gifts for Garden-Loving, Outdoorsy Dads

Dad doesn't need another tie. Find the perfect garden-centric gift that he'll want to use year-round.

The Makings of a Patio & Garden That Feels Like Home

Find all you need to make your patio feel like an extension of your home with Plow & Hearth. From sloped-arm sofas, drapery and solid wood dining sets to planters, garden arbors and all-weather artwork recommended by an experienced shopping writer.

The Best Cedar Planters for Every Garden Space

Cedar is one of the most reliable materials you can choose for outdoor planters. Here are the best cedar planters you can buy online, from raised beds to compact containers.

10 Beautiful Garden Fountains for Every Budget

Create a relaxing getaway in your own backyard with the help of an outdoor fountain.

7 Mistakes That Are Ruining Your Vegetable Garden Yield

Your plants might look healthy and still be underperforming. Here's what's cutting your harvest short and how to turn it around before the season's over.

The Best Landscape Fabrics for a Weed-Free Garden

Skip the endless weeding and let one of these landscaping fabrics do the hard work for you.

12 Garden Trellises for Climbing Vines, Blooms and Vegetables

Add support and style to your landscape design with these beautiful garden trellises.

8 Best Garden Forks of 2026, Tested and Reviewed

A good garden fork can save your back and your plants. Here are the ones that are worth adding to your shed.

9 Best Garden Trowels of 2026, Tested and Reviewed

Find the right trowel for every garden task, from everyday digging to heavy-duty root cutting.