Try one of these organic fertilizers this season
Question: I grow a lot of plants in containers, including lots of flowers, herbs, and vegetables. I have about 30 pots in all. I recently heard on your radio program that Miracle-Gro fertilizer is not organic. I mix it with water to fertilize my containers during the summer. Is there something else I can use instead that's organic?
Answer: You can fertilize your containers organically in one of two ways. First, when you fill your containers at the start of the growing season, blend your potting soil with high-quality compost. I mix mine at a 50-50 rate. The compost helps reduce irrigation needs and adds beneficial microbes, organic matter, and nutrients to the container. You can also mix two to three tablespoons of organic granular fertilizer into that soil blend as well when filling each of your containers. There are several different brands of organic granular fertilizer on the market, including Jobe's Organic All-Purpose Fertilizer, Espoma's Organic Garden-Tone, and Burpee Organic All-Purpose Plant Food, among many others.
Another option is to use a liquid organic fertilizer when you irrigate your containers. Liquid fertilizers are absorbed into plants via both their roots and their foliage. In general, nutrients provided to plants via a liquid solution are more readily, and more rapidly, available for plant use.
Using organic liquid fertilizers means a reduced risk of fertilizer burn and a more balanced “diet” for your plants. In addition to supplying the three macronutrients, unlike the synthetic chemical fertilizer you used in the past, most natural liquid fertilizers are also chock full of dozens of trace nutrients, vitamins, amino acids and plant hormones, each of which plays a vital role in the health and vigor of a plant.
There are many different types of liquid fertilizers available for use on container gardens, but here are three of the most popular ones.
Liquid kelpor seaweed is created by processing sea kelp at cool temperatures. It's rich in many trace minerals and amino acids, and is a source of several plant hormones known to aid in shoot and root growth. Some varieties of kelp can grow several feet a day, but seeking out kelp products harvested in a sustainable fashion is never a bad idea. Research has shown that liquid kelp is adept at increasing yields and drought resistance. It's one of the least expensive, yet most highly beneficial, liquid fertilizers.
Fish emulsion is made when whole fish are cooked and filtered. Before the finished fertilizer emulsion is created, the oils and proteins are removed for use in other products, leaving the resulting fertilizer bereft of many of the amino acids, vitamins and hormones most beneficial to plant growth. Still, fish emulsion is a good natural alternative to chemical water-soluble fertilizers, albeit a smelly one. Because the aroma of fish emulsion is so strong, it's wise to use it only in the mornings, so the odor has time to dissipate before nightfall. Otherwise, every raccoon, opossum and cat in the neighborhood will happily dig up your containers in search of the dead fish that's most surely buried in them.
Fish hydroslate (or liquid fish) is another, less odorous, form of fish-based fertilizer. Instead of cooking the fish, they're digested with enzymes at cooler temperatures to make hydroslate products. Then, the partially dissolved fish are ground up and liquefied. Many of the oils, amino acids, vitamins, hormones and enzymes remain in the finished product. The result is a nutrient-rich fertilizer containing many trace minerals. The enzymes used in the creation process also help break down the fishy odor. That being said, it's still a good idea to use fish hydroslates in the morning for the same reason stated above.
Not only are each of these three products useful on their own, they're also quite valuable when combined with other ingredients. Natural liquid fertilizer combination products blend the products described above with ingredients like liquid bone meal, blood meal, feather meal, and rock phosphate to create a well-rounded fertilizer and growth stimulant. They're readily found on the shelves of garden centers and are an excellent way to provide plants with the nutrients they need. Some brands to be on the lookout for include Espoma's Grow!, Fox Farms Big Bloom, and Earth Juice to name just a few.
When using any natural liquid fertilizer, follow label instructions for mixing rates and application instructions. Generally, most liquid fertilizers are applied either by mixing the product in a watering can and watering by hand, or by using a hose-end fertilizer distribution system to automatically deliver the fertilizer with the irrigation water.
Horticulturist Jessica Walliser co-hosts “The Organic Gardeners” at 7 a.m. Sundays on KDKA Radio with Doug Oster. She is the author of several gardening books, including “Attracting Beneficial Bugs to Your Garden,” “Good Bug, Bad Bug,” and her newest title, “Container Gardening Complete.” Her website is jessicawalliser.com. Send your gardening or landscaping questions to firstname.lastname@example.org or The Good Earth, 622 Cabin Hill Drive, Greensburg, PA 15601.