How To Care For A Hoya Krimson Princess (Hoya Carnosa)

Hoya carnosa, the Krimson Princess of the wax plant family, is a crowdpleasing plant that’s making an elegant return to the limelight. Some of you may have spotted these in your grandparents’ homes in the 70’s and 80’s as they were popular during that time.

As one of the lowest-maintenance and most easy-care varieties of the Hoya carnosa species, we think the Krimson Princess could be a delightful, rewarding addition to your indoor gardening journey. Plus i’m sure you’ll enjoy the clusters of chocolate-scented flowers.

Now that this plant is making her way back into the homes, and hearts, of indoor plant parents, we figured it was time to give her the spotlight she deserves.

Getting the basics of care right will help you to grow a robust, happy princess, that brings joy to your indoor gardening for years to come. Here’s everything you need to know to keep this little princess happy and thriving in your home.

Hoya Krimson Princess Care Summary

Scent	Chocolate-like fragrance
Light	Bright, indirect light
Watering	Drought-tolerant. Water when the top couple of inches of soil are dry.
Soil	Well draining
Temperature	Typical home environment will be fine
Fertilizer	Well diluted liquid fertilizer
Humidity	40% humidity minimum. See below for how to achieve this.
Repotting	Soil or water. See below if it’s your first time.
Toxic	No

Brief Background: Hoya Krimson Princess

Hoyas grow wild across Australia, New Guinea, Polynesia, and the Philippines, and are native to Indonesia, China, India, Thailand, and several other south East Asian countries.

There are hundreds of species of Hoya—with the climbing, woody-stemmed Hoya carnosa being one—and as part of the Apocynaceae family, they’re related to milkweed.

Hoya carnosa’s tightly-packed ball of pink—or more rarely, white—clusters of flowers look like tiny candies before they bloom, and the flowers themselves have a fine layer of hair.

The nocturnal flowers produce a sticky nectar and a sweet scent that many indoor gardeners describe as vanilla custard, honey, or chocolate.

Indoor Vs. Outdoor Growing

Because Hoya carnosa Krimson Princess hails from a tropical climate zone, it performs best in warm, humid conditions. This makes it well suited as an indoor plant, provided that you can find it a spot with bright, filtered light.

Direct sunlight at the end of winter and start of spring can help encourage flowering in Krimson Princess, but it is important not to allow harsh summer sun to scorch the leaves of the plant. To find out more about flowering on fluerly.

Having said that, a small amount of direct sun is fine. As a variegated Hoya carnosa, Krimson Princess enjoys bright light more than her darker-leafed siblings, so north- and east-facing windows are preferred for the northern hemisphere.

It’s an avid climber, but can enjoy life in hanging baskets and pots, or when allowed to roam unfettered across a trellis or window sill.

If you decide to move your Krimson Princess outside in the warmer months, ensure you have a spot with dappled light, protection from direct summer sun, and shelter from drying winds.

Those that have been grown in hanging baskets can do well hanging in trees outdoors in summer—where they will receive ample light and warmth, but be protected from harsh sunlight on hot days

Soil For Your Hoya Krimson Princess

This plant is notoriously fussy about having wet roots. To protect your plant from this issue, ensure you have a good-quality free-draining soil.

An excellent mix for all is African Violet potting soil like this one on Amazon, with perlite and / or orchid bark. The African Violet soil blend is light and drains easily, maintaining moisture without getting clay-like or soggy.

Adding perlite and orchid bark both help to aerate the soil and allow lots of space for water (and roots) to make their own path.

Many indoor growers have their plant directly in substrate—with coco chips being one of the most popular.

Avoid sitting your plant in a wet saucer when growing indoors, too. Often, the biggest mistake indoor gardeners make is watering their plant and allowing it to sit in a saucer of water—which defeats the purpose of a high-quality well drained soil.

When the soil in your Hoya Krimson Princess pot feels dry to the touch—even when you burrow your finger in 1-2”—it’s time to water it. Saturate the soil slowly, until water runs out the bottom of the pot. Allow it to drain away, then place it back in its spot.

Watering Your Krimson Princess

Hoya carnosa have a trick up their sleeves: they store water in their waxy leaves.

If you forget a couple of waterings—or go away on an extended vacation—your Krimson Princess is likely to do just fine.

When it comes to watering, as is the case with many plants, too much watering is often worse than not enough.

Your Krimson Princess requires more water in the summer, when the weather is hotter and more humid, and you can scale back slightly in winter.

There is a common misconception that you can tell if it’s time to water your Krimson Princess when the leaves start to pucker.

Don’t believe it—any amount of drought that impacts your plant’s leaf structure is too much over an extended period. If it happens once or twice, it’s ok.

However, if you use puckering leaves as a constant reminder to water your Krimson Princess, you are severely damaging its longevity.

Humidity For Your Hoya Krimson Princess

These plants love a humid environment—thanks to its Indian and East Asian roots. In fact, they can tolerate a lot of neglect, provided you give them the high levels of humidity that remind them of home.

If your bathroom has enough windows and light, these are ideal spaces to keep a Krimson Princess and watch it thrive.

There are several ways to increase the humidity levels around your Hoya Krimson Princess—and one of these is light misting.

If you plan to mist it, it’s important not to mist it when it’s in flower, as the moisture can trickle into the flower rosettes and cause rot. Mist the plant once or twice a day on warm days.

A humidifier in the home is another way to increase humidity, although this is considerably more expensive than buying a spray bottle.

Placing your plant pot inside another, larger pot with some rocks at the bottom can help keep the roots dry while still storing a little extra moisture for humidity.

You can create a similar effect by keeping a small bowl of water next to your plants, but this—in most areas—isn’t practical or convenient. Finally, grouping a collection of plants together can help them to create a humid micro-climate.

Humidity / Watering Tips

If your plant is struggling, fulfilling its need for humidity and moisture can be a game changer. Here are the keys to proper watering.

1. Water in the morning, not at night. This allows excess water to evaporate throughout the day, and reduces the risk of your plant having damp feet all night. Consistently watering your plants at night also contributes to leaf spot.

2. Water the base and roots, not the leaves. The best approach is to use a gooseneck watering can to water around the base and roots of your plant.

3. Use room temperature water. Cold water on warm roots can shock tropical plants and cause them to drop leaves.

4. Don’t overwater. It’s possible—and actually really common—for people to kill their plants with kindness. If you miss a watering, don’t give it extra water the next time to make up for it.

5. Increase humidity levels by placing your plant in the bathroom, or amping up humidity in other ways. This plant will put up with a lot if you meet its need for tropical humidity levels.

Fertilizing

Over-feeding Hoya Krimson Princess can undo all your hard work when it comes to flowering.

Organic, gentle fertilizer or a heavily diluted (I usually cut by half) liquid fertilizer, like this one on Amazon.

Applying it fortnightly or monthly, is effective at giving a Hoya Krimson Princess the micronutrients it needs, without overdoing it.

If you’re really committed to growing the best possible flowers on your princess, there are bloom boosting supplements on the market that deliver a more concentrated phosphorus.

This needs to be fed to your plant at the right time to be effective.

Repotting Your Hoya Krimson Princess

These plants, much like the rest of the Hoya carnosa species, don’t like their roots disturbed. In fact, they thrive in a snug pot.

Don’t take this too far and leave your plant root bound, though. The general rule of thumb is:

• Do repot when roots begin to grow out the top or bottom of the pot
• Do repot if you notice signs of yellowing on the leaf edges
• Do repot if your Hoya carnosa is outgrowing its current pot
• Don’t repot if your Hoya carnosa is blooming
• Don’t repot in winter, when your Hoya carnosa is resting

To repot, select a pot slightly larger than the one your plant currently lives in—generally referred to as the next size up.

Don’t go to the largest pot size under the assumption that your plant will “grow into it”.

Sticking to the next size up allows your plant to stay snug, while still having enough space to absorb water and nutrients from the soil.

Repotting your Hoya Krimson Princess is fairly straightforward if you follow these basic steps:

1. Water your plant thoroughly two or three days before you plan to repot. This stops the plant from being dry and stressed when you transplant it to its new pot.
2. Remove it from its pot gently. If it’s started to grow roots out the bottom of the pot, this may take a fair amount of time. If you have a fairly flexible pot—like a nursery or grow pot—a few squeezes to loosen the rootball can help.
3. Partially fill a new pot with soil and water lightly and evenly. Set aside to drain.
4. Loosen the rootball of your plant lightly to help dump out the used soil. Don’t tease out the rootball, since Hoya enjoy their roots being bunched up.
5. Once you’ve knocked out the depleted soil, set your plant into the next pot so that the top of the rootball is in line with the top of the pot. Avoid sinking the rootball in the pot, as it will struggle to breathe when it’s settled.
6. Slowly add more mix around the rootball until it is snug and stable, and doesn’t wobble out of the mix or lean to one side. Ideally, your plant should sit in the center of the pot, and stand upright.

Since your plant and your soil have been watered prior to planting, avoid watering for a couple of days to give your Hoya time to settle. Then water thoroughly and allow to drain.

Propagation

Hoya Carnosas are easily propagated from stem cuttings, and the Krimson Princess variety are no exception.

The best time to propagate it, is while the plant is in its active growth phase—so mid-spring to mid-summer. If the timing is right, you have two main options for propagating your Krimson Princess: soil propagation and water propagation.

Soil Propagation

1. To start, fill a pot with the same type of high-quality, free-draining potting mix you use to grow your plant. Water the potted mix well, and allow to drain until it is thoroughly moist. Take care not to waterlog the soil.
2. Once the soil has drained, you’re ready to start the propagation process to grow healthy, vibrant Hoya Krimson Princess to fill your home or to gift to loved ones.
3. Start with a clean, sharp grafting knife or set of shears. Typically, these are sharpened using a stone, but there are several other methods used.
4. Sterilize your cutting tool of choice using either undiluted ethanol, rubbing alcohol, or isopropyl alcohol.
5. Simply wipe your blade(s) or dip in the alcohol, and allow to dry.
6. Cut a stem from your Hoya Krimson Princess. The stem should be healthy, and have 2-3 leaves on it. Make a cutting around 5 inches in length and remove any leaves on the lower ¼ of the stem.
7. Dip the bottom of the stem (the part that will be used to develop roots) into a quality liquid or powdered rooting hormone. If you don’t have any rooting hormone, you can skip this step.
8. Plant this end of the stem in the soil you prepared earlier, taking sure that no leaves touch the soil.
9. Place the pot in an area with bright, filtered light—preferably morning light, which is gentler on the growing young plant.
10. Keep an eye on the moisture of your soil, to ensure the stem has enough water to grow strong roots, without overwatering and rotting the stem before it has a chance to take root.

Water Propagation

Water propagation may be trending right now, but it is still a very effective method of growing your own plants without spending a dime.

1. Start with a clean (preferably sterilized) jar or glass. Fill it with clean, filtered water.
2. Take a clean, sharp grafting knife or set of shears. Typically, these are sharpened using a stone, but there are several other methods used.
3. Sterilize your cutting tool of choice using either undiluted ethanol, rubbing alcohol, or isopropyl alcohol.
4. Simply wipe your blade(s) or dip in the alcohol, and allow to dry.
5. Cut a stem from your Hoya Krimson Princess. The stem should be healthy, and have 2-3 leaves on it. Make a cutting around 5 inches in length and remove any leaves on the lower ¼ of the stem.
6. Place the stem in the jar, ensuring that no leaves are below the water line. You may need to secure the stem so it doesn’t bob around in the water.
7. Place the pot in an area with bright, filtered light—preferably morning light, which is gentler on the growing young plant.
8. Refresh the water when it becomes murky (there’s no need to replace the water every day, though).

Once the cutting has grown roots, you can remove it from the water and plant it into a high-quality, well-draining potting mix.

FAQ’s

Hoya carnosa are a robust, easy-care plant…most of the time. If yours is giving you a hard time, don’t despair! There are always solutions to our indoor plant parenting struggles, if we haven’t covered it here, let us know in the comments what your problem is and we’ll do our best to help you out.

Why are my Hoya Krimson Princess’ leaves turning red or black?

This can be a sign of too much sun, which scalds or scorches your plant’s leaves. Move it out of direct sunlight.

Why are the leaves of my Hoya Krimson Princess shrivelling up?

Generally, this is a sign that your plant is not getting enough water or is in too dry an area. Increase your watering frequency, add rocks to the saucer of your plant to catch water and increase humidity, or move your plant to sit with other plants to foster a more humid environment.

Why does my Hoya Krimson Princess look limp?

It could be that the roots have died. Check to see if your plant suffers from root rot, or the roots have died, by gently removing it from its pot. If this is the case, you can propagate healthy cuttings of your plant. If the roots look healthy, consider the level of light your plant is getting in its current spot.

Why is my Hoya Krimson Princess looking leggy and straggly?

Your Hoya carnosa is likely in search of light, and trying to preserve its energy to move closer to a light source. Try moving it closer to a bright spot for a few weeks, and see if this helps.

Why did the leaves suddenly fall off my Hoya Krimson Princess?

This typically means your Hoya carnosa caught a chill or has been exposed to a cold draft for an extended period.

Is Hoya Krimson Princess toxic?

There are many houseplants that are toxic to pets and small children, but Hoya Krimson Princess is not one of them. Having said that, you don’t want your children or animals eating the leaves or flowers of the plant.

How should I prune my Hoya Krimson Princess?

Hoya carnosas in general are low-maintenance, and can live for years without being pruned. If you need to prune your plant (for example, because you’ve got limited space for it to run amok in your home) don’t deadhead the flowers. This is because new flowers grow from the same spurs, and won’t regrow if you remove them. We recommend propagating your cuttings to grow new Hoya Krimson Princesses for your friends and family.

Why won’t my Hoya Krimson Princess flower?

Hoya carnosa only flower when they are mature, so you won’t see blooms for the first 3-4 years of your plant’s life. After that, it’s a matter of providing the right conditions for optimal flowering. Hoya carnosa Krimson Princess requires bright, filtered light during the day, snug roots, and humidity to thrive. With the right care and conditions, your Hoya will be flowering in no time.

Advanced Tip
If you have been patient and pro-active in providing the right growing environment and care for your plant, and you’re still not seeing any flowers, you could try exposing your plant to a small amount of “stress”. An hour or so of direct sunlight in spring should do the trick, or try some bloom boosting fertilizer to hurry things along when you get too impatient.

I’ve been told my Hoya carnosa is a Krimson Princess and a Krimson Queen. How do I tell the difference?

Krimson Princess wears the white and yellow of her leaves in the center, and Krimson Queen wears her variegation around the edges of the leaves.
What tips do you use to get your Hoya Krimson Princess flourishing? Share them with our community below!