Hidden Valley Hibiscus

Plant Care

Potting & Planting Hibiscus

You just got your first exotic hibiscus plants, and now your first decision is whether to keep the hibiscus potted or to plant it in the ground. Hibiscus are tropical plants, so if you live in a place that freezes in the winter, the answer is an easy one - keep your hibiscus in pots that can be moved to a warm spot during winter freezes. If you live in a warm place that rarely freezes, and just barely hits 32° one or two nights per year at the most, then you have the option of planting your hibiscus in the ground. There are good reasons to keep them potted, such as being able to move them around, but we have also found that hibiscus do very well when planted in the ground in warm climates.

Planting Hibiscus in the Ground

In Warm Areas Hibiscus Thrive in the Ground

Before you plunk your hibiscus in the ground, it is important to spend a little time selecting and preparing the planting hole. Never forget the gardening wisdom of the ages, "It's better to place a $5 plant in a $20 hole than a $20 plant in a $5 hole." Here are two simple tests you can do to make sure you are planting into a hibiscus-safe spot:

Test your Drainage: Test the hole to be sure it drains by pouring a gallon or so of water into it. If the water disappears within an hour that is good enough. If it is still standing there after an hour you are probably planting into clay or over some other impermeable material, and may end up drowning the hibiscus roots. Alternatives are to build up a raised planting bed or to amend the soil with "clay-busting" material available at most nurseries. If the hole drains well, plant the hibiscus fairly deep, covering the original root ball with a couple of inches of soil as you fill in the hole.

Test Water Permeation: Test to see how well water soaks into your soil by digging a small well into the top of the ground. Fill the well with water 2 or 3 times and let it drain away for half an hour or so. Then dig into the soil, and look at the water line to see how far down the water has soaked. If the water is moist 8-10" down, then your soil has good permeability and it's safe to plant hibiscus in it. If only the top inch or two of the ground is moist, your soil does not have good water permeability, and your hibiscus could die of drought, no matter how much you water, because the soil resists soaking up any water you pour onto it. Before you plant your hibiscus, you will need to dig a very large hole that you fill with a high quality planting mix, allowing plenty of extra room for the hibiscus to grow roots into.

Super Sandy Soil: If your soil is very sandy, you will probably have problems growing hibiscus in it. Very sandy soil does not absorb much water or hold fertilizer. Most of the water applied to sand flows down past plant roots, and the water that is absorbed evaporates quickly. If you have very sandy soil either grow your hibiscus in pots, or be prepared to water often and use timed-release fertilizers on the surface of the soil. You can also try amending the sandy soil with good compost and other organic ingredients so that it will hold more water and fertilizer. Check with your local Dept of Agriculture and the Master Gardeners group in your area for more advice.

Digging the Hole: The hole you dig for your hibiscus needs to be a few inches bigger than the plant pot, on all sides, if your soil is good. If you are filling the hole with planting mix, make the hole much bigger than the size of the pot. If you live in a dry place where your hibiscus could get brushed with frost and where water retention is important, plant your hibiscus deeper into the ground, with the crown of the plant, where the roots meet the trunk, an inch or two under the surface. If you live in a soggy, warm place, dig a more shallow hole to keep the crown above the surface level of the ground around the hole. The more you break up and work the ground around the hole, the more easily your hibiscus will be able to grow longer, deeper roots. So take your time, and dig a $20 hole! Then put a few inches of good soil or planting mix into the bottom of the hole for your plant to sit on.

Ready to Plant: Once your hole is prepared, water the hole to moisten the soil all through it before putting the hibiscus in it. Gently remove your hibiscus from its pot, being careful not to rip the roots away from the base of the plant. As tempting as it may be to pull on the plant trunk to get the plant out of the pot, resist the temptation. Instead, put your hands on the soil, and gently turn the plant upside down up in the air. Then hug the pot, and let gravity drop the plant out of the pot into your hands. Use your hands to break up the roots around the rootball a little bit on all sides, then position the plant in the prepared hole.

Look at your plant before you finalize the position. Look which way branches grow, and make sure you position in the direction that looks best from what will be the viewer's vantage point. If the plant has listed to one side in the pot, use this replanting opportunity to make it stand up straight again in the hole in the ground. It won't hurt the plant a bit for the roots to be put a bit sideways into the hole. Take one last look at the position of the plant, then fill it in with soil somewhat firmly, but without heavily packing or tamping it down. Water very well - deeply, 2 or 3 times to make sure it completely saturates all parts of the hole and rootball. Et voilà! You're done! Wait a week or two before beginning your fertilizing regime, then fertilize away. Hibiscus rarely experience transplant shock. They love to have room to spread out their roots, and you will often see a recently planted hibiscus stand up taller and look happier than it did in its pot!

Keeping Your Hibiscus in Pots

A Happy 'Her Majesty' in a Pot

You May Need to Transplant to a Larger Pot: If you decide to keep your hibiscus in pots, consider transplanting them into larger pots. Except in special situations, pots 8" wide (approximately 2 gallons) or larger are needed by most varieties of hibiscus to do their best. At times we have been amazed to see the difference in our flowers once the plants had room to grow larger root systems to provide the hibiscus with all the water and nutrients they need. Gently ease the pot off the root ball. If the roots are circling the bottom of the pot and form a solid mass at the bottom, it is time for a larger pot.

Choosing the Pot Size: Choose a pot that is about one size larger than the one the plant came in. If it came in a 2-gallon black nursery pot, good choices for the new pot would be 3-gallon or 10-12" pots. Clay is good for stability, but the hole in the middle is usually not sufficient for good water drainage. Any pot you choose could benefit by having more drain holes. -If there is someone around who can drill more holes in the pot then go ahead and do so. If not, choose a pot that has at least 4 holes already in it. Our favorite option for repotting is to use a plastic pot and place it inside a larger, heavier clay pot which keeps it from blowing over in the wind and from overheating in the sun.

Choosing the Right Potting Mix: When it's time to transplant your plants to a larger pot, the most important thing is to use good quality potting mix that drains well. You can find this at good nurseries, or if in doubt, you can get our HVH Recommended Potting Mix. This is the potting formula we developed and mix ourselves for our own use in our greenhouse. After much experimentation, we found the ideal potting mix creates a balance of both water and air within pots. It has the ability to hold and transfer nutrients to the plant roots, and many organic compounds to protect plant and root health and to maximize growth. We prefer and mix a "living mix" that contains many beneficial microbes that plants need to thrive.

There are special dynamics at work inside pots - much different from what happens in the ground. For that reason good potting mixes are "soil-less". Instead of soil, they are usually made from coco coir, composted bark, or peat moss, with other material like perlite added to it. Unfortunately, most potting soils on the market are too heavy for our exotic hibiscus and stay too wet. If you decide to use such a product, it is important to add sharp clean sand, perlite, or bark in order to open up the mix and allow it to drain and breath better. Usually, adding 1 part sand or perlite to 3 parts purchased mix will be sufficient. Alternatively, a mix made for cactus can be used for hibiscus, although keeping the plant wet enough in hot weather could be a challenge with such a mix.

How to Repot Hibiscus: The actual repotting is a simple operation and can be done in just a few minutes. Merely place some of the new potting mix in the bottom of the new pot, so that the top of the root ball will be about 1 inch below the rim of the new pot when it is placed on top of the new soil. After settling the root ball on top of the new soil, gently fill in around the sides of the root ball with more of the new potting mix.

IMPORTANT: DO NOT jam the mix down into the pot. Air is as important as water to the roots, and tightly packing the soil mix will force most of the air out of the pot. Just fill in and lightly press on the soil so that the root ball is securely nestled in the new pot.

Water your hibiscus well to moisten all soil in the pot and the entire rootball well. Wait a week or two before fertilizing, then begin your regular fertilizing program.

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