Hibiscus have a great need for potassium in order to form strong, vividly colored blooms and sturdy enough branches to hold up such large flowers. Although our fertilizer already contains extra potassium, as our new hibiscus hybridizing produces larger and more colorful blooms, the need for extra potassium has increased. Some customers may want extra potassium to give their plants.
The question for a hibiscus lover is, how much potassium is actually good for the hibiscus plant? Erring on the side of caution, we are finding at HVH that quite a lot is actually needed by hibiscus, although of course, anything “good” can easily be overdone. Below is the exact formula we are using at HVH with our test flowers, for those who may wish to try it out. Our results have been good enough so far that we feel others may want to try the same formula. If you do try this formula, please email us and let us know how it works for you over time!
FOR USE WITH EVERY WATERING: Add to every gallon of the irrigation water:
~ 1/2 teaspoon HVH Special Blend Fertilizer
~ 1/2 teaspoon HVH Hibiscus Booster
FOR USE ONCE OR TWICE PER MONTH: Add to every gallon of the irrigation water:
~ 1 teaspoon HVH Special Blend Fertilizer
~ 1 teaspoon HVH Hibiscus Booster
Potassium increases the strength of cellulose and cell walls in plants. Cell walls are filled mostly with water, so stronger cell walls are able to be more fully hydrated. In woody plants, like hibiscus, stronger cell walls make stronger fibers that grow in criss-crossed layers to build stronger wood. It is through this mechanism that potassium helps grow stronger wood, stems, and branches on hibiscus. We are still in the process of testing the ability of our Hibiscus Booster to decrease the “legginess” of our floppier hibiscus, but so far the results look promising. Over the next year, we will continue our testing in this area.
A lot still seems to be unknown about the biosynthesis of pigments in flowers, but it is known that potassium is involved in the formation of the different types of pigment cells. Potassium is known to be on of the factors that turns on certain enzyme processes, including those that build pigment cells in certain plants. Apparently hibiscus are among those plants. Hibiscus aficionados have known for years that potassium increases flower size and deepens color and have used it before shows to maximize the beauty of their flowers. In time, science will discover the exact mechanism for this effect.
Our Hibiscus Booster contains potassium nitrate, a very soluble form of potassium. We have always included far more potassium in our HVH Special-Blend Fertilizer than is found in commercial fertilizers, but it is impossible to get as much potassium into our fertilizer as hibiscus optimally like. Extra potassium produces larger, brighter flowers and more of them. Varieties that become washed out in low winter light will brighten up closer to summer levels with extra potassium. Seeing is believing! Try it for yourself. As always, we obtain the best quality material available to offer you – a highly soluble, greenhouse grade potassium nitrate product that is chloride free, an important consideration for hibiscus growers.