News from Hidden Valley Hibiscus

Potassium ~ The Least Understood Plant Nutrient

And the Most Neglected!

Potassium is the least understood of all plant nutrients, plus it is expensive to put into fertilizer. So it has been the most neglected nutrient in plant fertilizers. Other plant nutrients end up forming part of the actual molecules and cells that make up plants, but potassium is not found in any molecules anywhere in plant tissues! So why is it important? We never really knew before. Only experience over time taught farmers that plants go downhill, stop producing, and eventually die without potassium. Finally now plant science is advancing, and little by little we are learning more about this unusual nutrient.

Potassium makes plants healthier in every way ~ lush green growth, more blooming, bigger flowers with more colors.

All Plants Need Potassium, Not Just Hibiscus

For years we have been telling hibiscus gardeners about the extreme importance of high levels of potassium for hibiscus, but it turns out that potassium is just as important for other plants too! It is the most neglected of all plant nutrients for growers and gardeners of all kinds of plants. Scientists and growers are discovering that many (possibly most!) plants need to have more even more potassium than nitrogen in their fertilizers.

So what does potassium do? Why is it so important? There's still a lot we don't know, but one thing we do know is that plants suck up huge quantities of potassium if it is available in the soil. The more a plant grows, the more potassium it needs. The more the roots grow, the more potassium it needs. The more it flowers and fruits, the more potassium it needs. This applies not just to hibiscus, but to most, or perhaps, all plants. Potassium must be extremely important in all aspects of plant growth because of the huge need plants seem to have for it. So with the help of recent scientific research, let's see if we can pin down a little bit more about what exactly potassium does.

Potassium is the Key to Building Cell Sap

Potassium is found in the cell sap of plants. This is the nutrient-filled water that hangs out in the empty spaces inside cells. Cell sap can take up to 80-90% of the space inside cells. Potassium is key to the creation and maintenance of cell sap. Plenty of potassium keeps the cell sap spaces, or vacuoles, plump, full of cell sap, and able to hold all the nutrients that do so much to make plants healthy. We don't yet know all the important things that cell sap and potassium do, but here is what we do know:

Cell sap makes strong wood, stalks and branches:

Potassium makes all plants healthier, not just hibiscus. The California pepper tree in the left foreground received only potassium twice per month. The California pepper tree in the right background received no fertilizing. After 2 years, the left tree built taller, stronger, more upright wood, many more berries, and darker & glossier green leaves. The tree without potassium at right had weaker, sprawling branches, less growth, fewer berries, and lighter & duller green leaves. Potassium alone built a much stronger, healthier tree, even without any other fertilizer.

Protein and amino acids are stored in cell sap:

Flower pigments are stored in cell sap:

Glucose is stored in cell sap:

Cell sap helps drive away predators:

Cell sap recycles plant parts:

Cell sap stores toxic substances that fight off predators:

Potassium is the Switch that Turns on Many Plant Processes

Potassium is a little chemical switch, called a co-factor, that switches on processes all over the plant, from photosynthesis to building of proteins, creating sugars, transporting nutrients, storing energy, storing sugars, and many more. It is a co-factor in more than 60 different processes in plants ~ way too many to list here. Scientists will surely soon discover many more that we don't yet know about! In order for plants to grow, get nutrition, use energy for flowering, and everything else plants need to do, they have to have plenty of potassium at hand, all over the plant, to switch on every one of these processes.

Potassium is the Transport Supervisor for the Whole Plant

Potassium is involved in every aspect of transport in a plant, moving food, nutrients, and chemicals all through every part of the plant. Plants don't have little pumps in them to move nutrients around - they don't have a heart that pumps like animals do. So they move nutrients by a passive process called osmosis, aided by potassium. Potassium floats as free ions in the water all through the plant, and pulls water and nutrients in its direction. Where there is more potassium, more water and nutrients are pulled - into cells, up into the plant from the roots, wherever water and nutrients are needed. Potassium is necessary to keep every single part of the plant properly fed and hydrated, from roots, stems, and stalks to leaves, flower petals, and each individual cell that makes up a plant.

Potassium Controls a Plant's Breathing or "Transpiration"

Plants "breathe" or transpire through tiny holes all over all the leaves called stoma. When a plant is plump and full of water, the stoma are wide open, pulling in maximum amounts of carbon dioxide to use to make food. When water levels are too low, potassium makes the stoma close up to seal off any loss of water and prevent the plant from dying of thirst. When water levels are high again, potassium opens the stoma back up so the plant can start to make food again. It is because of potassium that our plants go limp when we forget to water them, then pop back up again when we remember to water them. This does stress our plants, but thanks to potassium, they don't die!

Potassium Provides Some Frost Protection

Potassium helps protect a plant from frost in several ways. First, it helps plants make more sugars, and sugar is a natural anti-freeze. When the cell sap has plenty of potassium, the plants can store more sugars, packing more of this sweet anti-freeze into each cell of the plant. In addition to this, potassium itself functions as an anti-freeze! So a cell that has a lot of sugar and potassium both will have the strongest possible anti-freeze protection and can survive light frosts easily.

Potassium, potassium, potassium! For gorgeous hibiscus plants, use plenty of it!

Just Remember ~ Potassium, Potassium, Potassium!

This article is very long, and few of you have probably made it all the way to the end! It would take many more pages to detail everything we know about potassium in plants, and scientists have only just begun understanding this important nutrient. More information will surely be pouring in over the coming years. But whether or not we fully understand how potassium works, we really just need to understand that it is one of the very most important nutrients that all plants need in order to be strong and healthy.

So Your Hibiscus Order Just Arrived

What do I do next?

UPS dropped the box off and you can't wait to see what is inside. Fine, but please don't rush - getting the plants safely unpacked is important.

'Fuchsia Delight'

First, before you open the box, find the arrows to identify the top and bottom. The best way to unpack our boxes is to cut the bottom of the box open and then slide the box up and off of the plants. If you cut the top open and try to reach into the box there is a chance you will break the stems of the plants or poke yourself with the bamboo poles. By cutting the tape at the bottom and lifting the box off the plants, you will avoid these problems.

It is very important not to lift the plants out of the box by their stems. This can cause damage to the roots of the plant that can kill the plant. Pick the plants up by grasping the pots, not the stems.

Most of our boxes have a top and bottom that can be opened and the above technique is the best way to go. However, a few of our boxes actually open and close on the side. If your plants came in one of those then it is easy to open the sides and slip the plants out of the box that way.

'Meteor Shower'

Now the box is off the plants and the plants are standing on the ground. The bamboo poles are sticking up. All you have to do is pull the poles straight up and out of the pots. You may want to save these poles to use as stakes for young plants in the ground if you live in an area with strong wind.

Next, untwist the twist ties holding the plastic bags in place, then remove the plastic bags from around the pots.