Hailing from tropical Southeast and East Asia is the pink and cream-colored Hoya Krimson Princess (scientific name: Hoya Carnosa ‘Rubra’). Treat this Hoya well and you’ll be rewarded with clusters of pink and red flowers with a heady milk-chocolate scent!
The Hoya Krimson Princess is a low-maintenance, easy-going plant. But sap-sucking pests are common, enticed by fragrant flowers and sweet nectar. You can ward them away using a neem oil solution. This variety is also susceptible to overwatering, so ensure the top 2 inches (5cm) of soil is dry before watering.
In this article, we’ll cover everything you need to know to help your Hoya Krimson Princess thrive!
Let’s dive into the details.
What is the Hoya Krimson Princess?
This Hoya Krimson Princess is the variegated version of the Hoya Carnosa. 🙂 Like many Hoyas, the Krimson Princess has thick waxy leaves that give Hoya plants their nickname, Wax Plant.
Needless to say, this houseplant is sought-after for its bright pink stems, as well as the cream and pink variegation in the center of the leaves! It grows long vines, so you can let your Princess trail down from a hanging basket.
Caring for your Hoya Krimson Princess
Light
Light is the one of the most critical factors for your Hoya Krimson Princess. Lots of bright indirect light (at least 6 hours per day) plus a few hours of direct light is perfect. Ours is growing well near an East-facing windowsill.
Small doses of direct light (1-2 hours in the mornings or evenings) coaxes more pink to form on its leaves. But don’t go overboard, as your plant will pale and scorch if the light is too harsh.
As a rule of thumb, variegated plants need more light, as those portions lack chlorophyll and cannot photosynthesize. You’ll need to compensate for this by giving your plant more light.
Water
There are two essential aspects of watering you should know about when it comes to your Hoya Krimson Princess.
But before we dive into that, take a look at your plant’s leaves. You’ll notice they are rather thick. These succulent-like leaves serve as a water store for your hardy Hoya Krimson Princess.
As a result, your Princess is tolerant of dry spells. At the same time, as an epiphyte, it hates being overwatered.
When and how to water your plants are important, and must be taken with a view of what your plant is used to in nature, and how to mimic those growing conditions.
When to Water
Knowing when to water your plant boils down to the same steps like many other houseplants.
- Before watering, use your fingers to check the moisture level of the top 2 inches of soil.
- Only if the topsoil is dry should you water your plant.
- When using this method, check the moisture level every 1-2 days when you first bring your plant home until you get more familiar with its watering tendencies. This is so that you know once the moisture levels change!
- Mornings are the best time to water your plant.
Keep in mind that wrinkled leaves, especially on leaves closest to the soil, signify that your plant is underwatered. At the same time, soft, yellow and wilting leaves typically mean your plant is overwatered.
Be careful to always use the finger-moisture test, because the Hoya Krimson Queen is easy to overwater!
How to Water
The second part of watering is the “how”. Use the soak and dry method.
- Water slowly and deeply near the roots until the soil is saturated and excess water escapes from the drainage hole. (Always use a pot with drainage holes!)
- Then, empty the saucer.
- There’s no need to use distilled water for this Hoya Krimson Princess; we’ve found that normal room temperature tap water is fine.
Should I water my Hoya in winter?
It depends if your plant needs water 🙂
In winter, water requirements drop as your plant slows its growth and may go dormant. Exact water requirements depend on how cold the winter is, evaporation rates, the type of soil you are using, and how much your plant is growing.
So it’s always wise to continue using the finger test to check if your plant needs water. If the topsoil is dry, continue to water your plant in the same way.
Humidity
Hailing from the rainforests of Southeast and East Asia, it’s no surprise that your Hoya Krimson Princess loves a humid environment. Between 70-80% humidity is ideal, encouraging vigorous growth.
Our suggestion? Invest in a humidifier if possible. Otherwise, check out other suggestions on raising humidity levels.
We prefer not to mist our Hoya Krimson Princess as light misting only provides a slight and temporary increase in humidity levels. Plus, wet leaves and flowers encourage bacteria growth and breeding.
For a plant that is already somewhat susceptible to pests and diseases, its just not worth it!
Temperature
Ideally, keep your Hoya Krimson Princess between 61-95 degrees F (16-35 degrees C). Thankfully, this ideal range falls within average indoor temperatures, so there’s likely nothing much you need to do here.
They are not cold-hardy, so bring your plant indoors unless you live in a temperate climate year-round (USDA Hardiness zones 10 and 11).
Cold drafts and chills can lead to leaf drop!
Flowering
If you’ve given your Hoya Krimson Princess optimal growing conditions and have been patient, you may be rewarded with flowers! You will need to wait around 3-4 years for your plant to mature before it will start to bloom.
Umbels of up to 30 small star-shaped, pink flowers with red centers bloom from peduncles (spurs). What’s more, these alluring flowers are fragrant, producing a chocolatey scent that is strongest in the evening.
The flowers produce sticky nectar, sometimes so lush that it drips down.
If you’ve been patiently waiting for flowers (after 3-4 years), here are some tips to encourage blooms:
- Sufficient light – the first and foremost reason why mature Krimson Princesses don’t flower is that there is insufficient light. Use a grow light if you need to supplement natural light.
- Don’t trim off peduncles; your plant re-uses the same spurs to bloom season after season. If you cut them off, they don”t grow back!
- High humidity of 70-80%.
- Use a phosphorus-based fertilizer which encourages blooming.
- Allow your plant to be slightly root-bound in pots.
Growth
Your Hoya Krimson Queen is not a rapid grower, but you can encourage it to grow more quickly by providing it with enough light, warmth, and humidity.
Indoors, your plant can grow up to 60 – 80 inches (1.5 – 2 meters). Though this is a far cry from the wild, it can grow to a length of 20 feet (6 meters)!
Although your Hoya is not technically a succulent, it has waxy and thick leaves that resemble succulents. Expect them to grow to around 1.5 – 2 inches (4-5 cm) long.
Being an epiphyte in the wild, your Hoya has a climbing habit. When kept indoors, you can choose to plant your Hoya Krimson Queen in a hanging basket so that its vines trail down.
Alternatively, use a regular pot and, when its large enough, use a stake, trellis or pole to support its climbing habit. Whatever you choose, remember to use a pot with drainage holes!
Soil or Growing Medium
Hoyas are our favorite plants to grow in LECA.
Being an epiphyte with aerial roots, your Hoya Krimson Queen needs to keep its roots breathable.
LECA provides the ultimate airy substrate and, when done right, provides a “false bottom” separating roots from the water underneath. This dramatically reduces the risk of overwatering.
Check out our guide on LECA pros and cons to see if this is a good fit for you.
If you prefer using a traditional potting mix, we suggest using an African Violet blend specially formulated to be well-draining. Then, add some perlite and orchid bark to lighten and aerate the mix.
- 1 part African Violet potting mix
- 1 part orchid bark
- 1 part perlite
Fertilizer
If you are using LECA, you’ll need to use a hydroponics fertilizer as LECA is inorganic, so your plant is more dependent on fertilizer for nutrient typically drawn from the soil.
If you are using a traditional potting mix, a gentle houseplant fertilizer will do. Choose a urea-free blend so harsh chemicals do not damage that roots.
We like using Dyna-Gro Grow, at half strength, once a month during the spring and summer months. Hold off fertilizing during winter and fall.
For those living in a tropical climate year-round (no distinct seasons as you live near the equator), you can continue monthly fertilizer application as long as you see your plant putting out new growth.
Repotting
Like most small vining plants, your Hoya Krimson Princess prefers to be very slightly root-bound. The added stress is actually positive for your plant.
However, once you see roots peeking out from the bottom of the drainage hole or circling above the soil’s surface, it’s time to repot!
Generally, this is once every 1-2 years. Spring is the best time for repotting.
- Water your plant the day before repotting – this reduces the stress on the plant.
- Place your plant on its side, and use your fingers to work through compacted soil until your plant can wriggle free.
- Prepare a new pot, just 2 inches larger than the previous, and partially fill with fresh soil.
- Set your plant in the new pot and add more fresh soil until the rootball is covered to secure your plant in place.
- Avoid watering for 3-6 days afterwards, as roots sometimes don’t function well straight after repotting. Your plant needs a few days to heal. Watering straightaway increases the risk of root rot.
Toxicity
Thankfully, the Hoya Krimson Princess is not toxic to pets and humans. Like all members of the Milkweed family, your Princess does have a milky sap that may be irritating for sensitive skin.
So when pruning or propagating your plant, use gardening gloves.
Water Propagation using Stem Cuttings
Stem cuttings are the easiest way to propagate your Hoya Krimson Princess.
We prefer using water propagation so that you can observe the development of roots before replanting into a permanent potting mix (or LECA).
The best time to propagate your plant is Spring. The warm, humid conditions and when your plant is actively growing increases the chances of successful propagation.
- Choose a healthy portion of the stem that has at least 2-3 leaves but NO flowers. Avoid any woody stems (these are thick and brown), and avoid any new stems.
- Using clean garden shears, cut off the identified part below the node.
- Dip your stem cutting in rooting hormone. This encourages roots to grow quickly.
- Remove any leaves from the bottom half of the stem cutting (as this will be submerged in water).
- Add room temperature distilled water into a jar.
- Place your stem cutting into the water jar, ensuring that no leaves are submerged. At least one node should be submerged.
- Place your stem cutting in a warm and humid location, with plenty of indirect light (but no direct sunlight). If you have a humidifier, place it next to the jar and set it at 75%.
- Replace the water every few days to prevent it turning murky.
- In a few weeks, you should see roots starting to grow.
- Once roots grow to 1 inch (2.5 cm) long, you can replant them in their permanent home.
- Prepare a pot (with drainage holes) with fresh soil and plant your stem cutting into the pot.
- Treat as you would any other Hoya Krimson Princess!
Pruning
Hoya Krimson Princesses are low-maintenance, and can live for years without being pruned.
However, it is a good idea to occasionally prune off damaged parts so that your plant can focus its energy on new growth.
Here are some pruning tips:
- Use sterilized shears (we use 70% isopropyl solution to sterilize) to prune off dead or wilted leaves, and leggy stems.
- Don’t deadhead flowers. Let flowers wilt and fall off naturally.
- New flowers grow from the same penducles (spurs), year after year. If you snip them off, they won’t regrow.
- You can use stem cuttings to propagate your plant 🙂
Common Pests and Diseases
Unfortunately, the sweet fragrance and sticky nectar of your Hoya Krimson Princess attracts many common houseplant pests. The usual pests that are especially attracted to the Princess are the sap-sucking variety, as they are attracted to the sugary nectar.
These are mealybugs, spider mites and scale.
If you encounter any of these bugs, read our step-by-step guide on using neem oil as a pesticide to eradicate them.
A dilute solution of neem oil can also be used as a preventative measure. While applying the oil, take the time to inspect your plants for any problems.
Early detection makes all the difference, given the extremely high reproduction rates of these pests.
Mealybugs
- Mealybugs are white, oval insects with clearly segmented bodies that are 1/10 – 1/4 inch long.
- They tend to cluster together on undersides of leaves, and hard-to-reach places.
- They especially love feeding on new growth, and softer parts of the plant.
- Mealybugs are attracted to warm climates.
- They like to attack overwatered and over-fertilized plants.
- As they feed, they secrete honeydew that stays on the plant and eventually attracts sooty mold, a fungus. Another reason to kill these pests ASAP!
For more details on how to identify mealybugs, check out our guide.
Spider Mites
- Related to ticks, spider mites are not technically insects, rather eight-legged arachnids.
- They love dry environments (low humidity) so dry winter months are favorable to these pests, although in summer, they reproduce more quickly.
- Being much smaller (1/60 to 1/25 inch) than mealybugs, they are harder to spot, and come in many different colors.
- A tell-tale sign that spider mites are present is the presence of fine webbing on the undersides of leaves.
- In addition to plant sap, spider mites also suck on chlorophyll, causing white spots on leaves. Other signs of an infestation include stippled, yellow and cripsy leaves.
For more details on identifying spider mites and getting rid of them, check out our guide.
Scale
- Scale insects are related to mealybugs. They are small, oval and flat insects with a brown armour.
- They especially like to gather on stems, under leaves and at leaf joints.
- Scale love dry (low humidity) and warm environments.
- If you’re brace, you can pluck them off or use a water spray to dislodge them.
- Like mealybugs, scale bugs secrete honeydew that leads to sooty mold.
Troubleshooting
Why are my Hoya Krimson Princess’ leaves shriveling up?
Shrivelled up leaves is a sign that your plant lacks moisture, either in the form of an underwatered plant or air that is too dry (too little humidity). Check the soil moisture to confirm.
Adjust your watering frequency, or use a humidifier to boost moisture levels in the air.
Why is my Hoya Krimson Princess leggy?
When your plant doesn’t get enough light, it grows long and leggy as it tries to reach for more sun. Use a grow light to supplement natural light so that your plant can grow bushy.
Why are leaves suddenly falling off?
This is usually due to too-cold temperatures or a cold draft. Relocate your plant to a warm spot with stable temperatures.
Why are the leaves yellow?
Yellow leaves in a Hoya Krimson Princess is most commonly a sign of overwatering. Check the soil moisture to confirm.
If your plant is chronically overwatered, you will need to consult our step-by-step guide on how to save it!
Frequently Asked Questions
Does the Hoya Krimson Princess live long?
Yes, when placed in optimal growing conditions, Hoyas can grow for decades.
How much does a Hoya Krimson Princess cost?
A Hoya Krimson Princess usually costs US$20-40 for a small pot. Well-established Princesses may cost more.
We like buying plants from reputable sellers on Etsy.
The Hoya Krimson Princess is slightly harder to find than the Hoya Carnosa, as demand for variegated versions skyrocket. Same goes for the Krimson Queen!
Does the Hoya Krimson Princess grow fast?
No, they are not rapidly growing plants. Giving your plant sufficient light, warmth and humidity are key ways to boost growth rates.
The Krimson Queen is a faster-grower!
Can a Hoya Krimson Princess revert?
Unfortunately yes, they can revert to an unvariegated, all-green version if these plants don’t get sufficient sunlight.
If yours is starting to revert, cut back your plant’s green leaves until the last variegated leaf.
This gives new growth the best chance of developing variegation. Ensure your plant is getting sufficient sunlight and nutrients (see Fertilizer section above) to encourage variegation.
Similar Plants and Varieties
Hoya Krimson Princess vs. Hoya Krimson Queen
The Hoya Krimson Queen and Hoya Krimson Princess are variegated versions of the Hoya Carnosa. They look the same at first blush, as they share the same cream, green and light-pink color palette.
Here’s how to tell them apart:
- Hoya Krimson Queen has variegated pink and cream leaf margins. Within the margins, its leaves have a green center. It also has a brown stem.
- On the other hand, the Hoya Krimson Princess is the opposite. It has has variegated centers with green margins. Instead of a brown stem like the Queen, it has a bright pink stem.
There are also differences in care conditions: the Hoya Krimson Queen needs more water and grows faster than the sluggish Princess.
Other Hoyas we Love
- Hoya Bella – The Honey Plant, a beginner-level Hoya with white flowers and a honey scent.
- Hoya Nummularioides – a great beginner plant with a strong jasmine scent.
- Hoya Serpens – round, button-like forest-green foliage with fuzzy green flowers.
- Hoya Curtisii – fleshy, olive-green leaves with silver splashes.
- Hoya Imbricata – this is an oddball with strange, cup-shaped leaves with mottled silver variegation.
- Hoya Pubicalyx
- Hoya Carnosa Compacta, the Hindu Rope Plant
- Hoya Obovata
- Hoya Linearis
- Hoya Macrophylla
- Hoya Krimson Queen
- Hoya Kerrii, the Sweetheart Hoya
Wrapping Up
The Hoya Krimson Princess is a beautifully variegated plant that thrives in warmth and high humidity.
- Light fertilization helps stimulate growth, as this plant is rather slow-growing.
- Having sufficient light is key. A few hours of direct light is beneficial but don’t overdo it.
- Use neem oil to ward away sap-sucking pests.
- Don’t mist this plant.
- Use the soak and dry method when watering. Don’t water until the topsoil is dry.
If you’d like to enjoy another Hoya with the same color palette – cream, green, and pink, try the Hoya Macrophylla.
Deborah is a plant enthusiast and founder of Gardening Collective.