Paphiopedilum: Care, Culture and Tips for Growing Paphs For Windowsill & Indoor Growers

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Ah, so you’re looking for some tips on how to grow Paphiopedilum slipper orchids, eh? Wonderful! I’ll avoid the back story of paphs to spare you some time—there are lots of other sites that cover those details; however, for a high-level understanding, Paphiopedlium orchids belong to a group called, “Slipper Orchids.” Within the slipper orchid cluster, there some non-paphiopedilum species which are native to the Americas and Europe; however, Paphiopedilums specifically are native to Asia (predominantly within Southeast Asia, the Indian Subcontinent, southern China, New Guinea and the cluster of islands within that geographic area). Another popular type of tropical slipper orchid you may find are Phragmipediums (native to South America) and those typically prefer slightly cooler temps and more moist conditions compared to paphs—but it really depends on each individual species as there are cold growing paphs and warm growing phrags! While both of these slipper orchids look similar, their flowers are distinct and their care is different, so just make sure the plant you have is either a paph or phrag and apply care as necessary.

Note: At the end of this article there are a bunch of photos of my plants if you want to see them, but with that let’s get into paphipedium care and culture.

Paphiopedium lowii
When I first got this plant, it was small, light stressed and I nearly lost it to crown rot within the first month. After some careful attention to watering and providing the care I’ll cover in the article below, it came through and finally bloomed 3 years later.

 

I love Paphiopedilums but let me tell you…they grow SO SLOWLY

 

Perceived difficulty – Are Paphiopedilums hard to grow?

Paphs get a reputation for being difficult to grow, but then people who have mastered their care, feel they’re very easy to grow. So what its it—difficult or easy? Well…that really depends on your expectations of the plant and your ability to provide consistent care over a long period of time—I consider them easy NOW…but for years I struggled to grow them well AND I had a hard time finding the core advice needed to “unlock the power of growing paphs.” So, let’s break it down so I can convey some of my experience to you and hopefully give you some perspectives that may improve your chance for success.

Expectations of Paphiopedilums

  • Paphs grow slowly: on young plants, they are especially slow and it may take a “seedling size” or “near blooming size” plant many years to finally bloom for the very first time—like we’re talking 8…10…15 years in some extreme cases! Most species will bloom much sooner than that, so don’t be discouraged. After the first flowering, then you’ll generally get one or two new growths per year from each previous crown; this means a plant that has 2 existing growths may produce 2 to 4 additional growths the next growth cycle…and they size up “quickly” after that, doubling size about every year or…three. BUT…to get a paphiopedilum to flower for the first time can be a test of your patience. Fast growing paphs may produce a new leaf every month or two, and new leads (pups/offshoots/crowns) will be produced about once every year or two. Some slower-growing species may take 2 or more years to develop a mature growth, but generally they fall into an annual cycle of: new growth, flower, pause, repeat.
  • They spike once per growth: each new growth will spike and flower once only from the crown as that section of the plant matures. Depending on the species, a spike may put out a single flower, a series of sequential blooms, or a cluster of flowers which open at the same time. You will only get one flush of flowers per crown and once that spike dies it will not flower again from that same growth.
  • Some Paphiopedilum flowers are fragrant: but most are not. I recommend, if you have one in flower, give it a sniff. I have had flowers that smell like alfalfa or cut grass (paph primulinum var purpurascens), or black pepper (a henryanum-rosthchildianum-primulinum hybrid), and I’ve heard of some that smell like green apple or strawberries. So…just give it a sniff because you might be surprised at what you find.
Paph Delophyllum and other paphs near a South window
(which has since been “screened” to reduce the intensity in the summer)

 

Paphiopedilum Care – Consistency is Key

Understanding that paphs are both slow growers and that they only spike once per new growth, comes the next tricky component…Paphs need really consistent care year-round. You can’t forget about them for half the year and start watering them in the spring. They grow slowly but need very consistent conditions to maintain that slow but progressive growth through the spring, summer, fall and winter.

One of the challenges with this for me is that…they aren’t very responsive plants; I’m used to plants really showing off when they’re happy, but with paphs they are always in a state of “the same” until they flower. If you’re expecting a validating plant that shows it’s appreciation in weeks and months…Paphs may not be for you. You’ll measure success more in years and possibly decades, but when they do flower…wow, it’s years of commitment that’s made that happen and you may find THAT more rewarding than growing any other plant.

If you’re the type of person who frequently forgets to water your plants…don’t start with a paph. It’s not going to go well—and I can tell you this because that’s how I started and I killed a lot of paphs. The problem is, by the time you can see that a plant needs to be watered (withered/leathery leaves), the damage is done; root tips have aborted, some may have possibly died off and because the plants aren’t aggressive rooters, if you lose the few roots they do have, it’s pretty much doomed.

So… TL;DR: Paphs are great for people with a routine.

 

Basic Care for Paphiopedilums

Watering & Hydration

Your goal is to have “moist roots, but not constantly wet or dry.” BUT WHAT DOES THAT EVEN MEAN??? This was so confusing for me when I started growing paphiopedilums. Understanding, “Not dry, always moist, but not wet.” was especially challenging because in my dry Alberta climate, the difference between all three extremes is literally a matter of waiting 24-48 hours.

So let me help clarify this…with some watering tips

    1. Don’t let the roots hard dry! If the roots are “bone dry” like a phalaenopsis, you should have watered yesterday, and you really need to observe the dry-out tempo in your climate and then avoid letting the plant get that dry in the future. Using clear orchid pots will help with this – if you don’t see condensation on the pot between the media or if the roots in the middle/bottom look dry, it’s time to water.
    2. On watering day soak the whole pot in water up to the base of the plant for at least 5 minutes. My 4.5″ pots fit perfectly in a coffee mug, so I plop the pot in and drench the media from the top until the mug is full and then I let them soak for at least a good 5-10 minutes. If your climate is especially dry (under 50% rH), then you can let them soak for them for a good 20-45 minutes without causing issues.
    3. Anaerobic conditions cause root rot…not water (we’ll cover this in potting media below).
    4. Calcium, nutrient deficiencies and low pH cause root rot…not water (we’ll cover this more below).
    5. When watering you want to actively irrigate and flush lots of water through the pot to help oxygenate the roots AND to waterlog the bark. When bark is saturated, it will release that moisture over the week creating a microclimate of high humidity in your pot. That means “dribble watering” is probably not as effective as it may create a bottom section that’s moist, with a top section that’s bone dry. You want to drench all the bark so the whole pot is evenly moist (allowing the short new roots to succeed as well as older longer ones). Soaking and flushing your pots about every 5-10 days is very helpful for keeping your roots healthy while avoiding drought, and the soaking action allows your plant to rehydrate if it’s slightly dehydrated. You may need to adjust that watering cadence based on: your own climate, on the size of the pot, on the type of pot (terracotta really SUCKS water out of the potting media while plastic pots trap moisture), and on the size of the potting media. Please don’t read that and think you only need to water your paph every 10 days… if you’re using a small pot with large bark chunks and your humidity is 30%, you may need to water that plant every 2 days just to keep the roots moist.
    6. Keep roots moist longer: Once you’ve soaked and drained the potting media you can leave an additional 1/8-1/4 inch of water in the tray. Applying this nugget of advice fundamentally changed how my paphs grew…and I have both Barbara Bielecka and Neil Kim to thank for instilling that advice in me (thank you, paph gurus for sharing your insights). It’s a very powerful tip if you understand the goal—which is to keep the roots consistently moist between waterings, while also keeping them oxygenated. You only want to use enough water that it will dry up within 24-48 hours, AND initially you should pay very close attention to this practice to avoid using too much water. The goal isn’t to have the pot sitting in water all week long and if you watered on Sunday and there is still water there Wednesday morning, you should dump it out and use less water next time. Seasonal changes may also alter your evaporation rates, so beware that what works in winter may need to be adjusted in the summer.
      • Before I started doing this, I used to have paphs that would only grow spurts of roots in the spring/summer. However, now that they’re evenly moist all week long, they grow roots year round.

Watering Frequency: “How often should I water my paph?” – For me, I’ve perfected a potting mix that allows me to water once per week (sometimes twice for the seedlings). For you, like I mentioned above, the frequency will depend on your potting mix, your climate, and your general lifestyle. Some people enjoy watering their plants often and they will use a chunkier media that dries quickly. I will say…if your potting media is taking more than 10 days to dry, then you may have to contend with anaerobic conditions because it could mean airflow is poor or the media has compacted—repot if in doubt.

Humidity: I’ve left this until the end of the hydration section because while most care guides say “high humidity is required”, I’ve found that not to be true (as long as you keep your plant hydrated and avoid drought). You can see that much of this care sheet focuses on hydration, watering tempo, and avoiding extremes of wetness or dryness at the roots…this is how I’ve been able to grow paphs well in my very dry climate that rarely exceeds 50%rH and often sits around 20-35%.

As with care for all tropical plants, if you can increase your humidity then YOU SHOULD, it will probably make it easier to care for the plant week over week and lessen the chance of extreme drought. However, from my experience growing a wide range of rare plants and paphs for many years (including paph lowii, philippinense, henryanum, tigrinum, primulinum, helenae, and a bunch of hybrids), low humidity isn’t a death sentence so long as you can avoid hard drying of the roots.

Paph helenae growing in live moss
Despite my humidity being so low, my irrigation practice even keeps live moss thriving. If you like the look of this pot, check out my post on how to grow live moss.

 

Light – How much light do Paphiopedilums need?

Everything I read says paphs like “low light”. In my experience they like intermediate light…bright enough to encourage vibrant leaves and vigorous growth, but not HOT enough that it will burn the leaf. So what does that mean? East-facing windows with direct sun for a small portion of the morning seems to be good, or South/West windows with a sheer cloth that screens at least 50% of the sun. LED grow light are especially helpful because you can provide long hours (10-14h) of consistent low-to-moderate light, but you only need about 8-20 watts per square foot of coverage. If you really want to dive into light, I’ve written a great post on the topic as it applies not only to paphiopedilums, but all houseplants; here’s a link to Light Recommendations: PPFD (PAR) for Orchids and Houseplants.

Also as a general note on the light requirements of different types:
* Mottled leafed paphs generally need lower light than strap-leafed paphs.
** Sequential-blooming papsh do well with low-to-moderate levels.
*** Strapped-leafed (multi-floral) paphs generally need bright light—up to cattleya levels in the fall during inflorescence formation.

Potting Medium – What potting mix do paphs need?

I mentioned above that paphs need good airflow at their roots. They typically grow as epiphytes (on trees with their roots covered in live moss) or lithophytes (on rock with their roots also covered in live moss), but many are terrestrial and grow in a mix of leaf litter, decaying forest bits, rock and again…moss. What all of these will typically have in common is that they are water-retentive but well draining (not dense, muddy or compact), and no matter what, they get rained on often—with many species coming from places that have seasonal monsoons where it rains daily for weeks or months at a time! Your potting media needs hold water, but allow for drainage and airflow too, so the roots don’t choke and rot.

My recommended media: I use a baseline blend and I’ve been tinkering with it for a few years now. It’s roughly 50% bark to 50% rock (pumice or large perlite), with a top-dressing of sphagnum moss around the base of the plant. The sphagnum helps keep the base of the plant moist (where new roots start) and it slows evaporation a bit, but it’s only a thin layer of about 1/8-1/4″. For bark I prefer Orchiata (pine bark) because it lasts longer and retains water more reliably than fir bark (which can fragment and get soggy as it ages faster than pine bark). If I have horticultural grade charcoal available, I’ll also add that in place of some of the rock (up to 5% of the total media ratio).

Photo of orchid media: perlite & orchid bark

 

Additional potting media tips:

    • You can optionally also add a small amount of peat moss or fragmented sphagnum moss to the bark/rock media if you’re finding the potting media just dries too fast—but no more than 5% and again, if the media is staying moist for more than 10 days, you definitely should repot and not use this option.
    • You can read more about paphiopedilum potting mixes here.

When to repot? This is a good question…most people will tell you to repot paphs every year. I only repot every 2 or 3 years. However, I use alkaline water (which means the potting media doesn’t get acidic because the pH is constantly buffered up by the calcium in my water), and at least 50% of my potting mix is rock (which gives structure and doesn’t enable compaction as the organic ingredients decay). So…to be safe, repot annually. If you’re going to repot less frequently then use a well draining media with more inert additives like we just covered, and consider adding oyster shell too to prevent acidification of your media…we’ll get to that in the next section. Also, repot frequently enough to avoid pot-bound plants; if the roots circle around the inside of the pot too much, they will create a barrier which could set future root growth back—ensure a plant has enough space to expand roots, but not overpotted with so much space that the media takes too long to dry out.

Photo of Paph roots on repotting day
Freshly repotted w/ a top-dressing of sphagnum moss

 

Fertilizer – How to fertilize Paphiopedilums

As with most orchids, fertilize “weakly, weekly” (which means about 1/4-1/2 strength the recommended dose – for paphs it’s even better to tread closer to 1/8 the recommended does). Some paphs are known to be sensitive to salts and unfortunately by the time you know something is wrong, the plant is already severely stressed.

    • Synthetic feed: I mentioned I use tap water for my paphs and it’s alkaline (7.5-8.3pH w/ 200-250ppm total dissolved salts) so I use 1/8tsp to 1/4tsp of MSU orchid fertilizer per gallon (4L) of water. After a feed, I’ll follow the next two waterings with just water (which flushes and removes the old fertilizer).
    • Organic feed: I also add a bit of organic fertilizer 2-3 times per year (at spring, early summer, and when I repot a plant). If you follow Ed’s Orchids on YouTube, he also does this and his plants are amazingly healthy. If you haven’t checked out his channel, you should, it’s a great resource for paph care in general. The organic fertilizer I use is called, “Gia Green’s All Purpose 4-4-4″ and it has bat guano, bloodmeal, rock dust, oyster shell, and a bunch of other goodies. If you don’t have access to this product, seek out bloodmeal, oyster shell, and rock dust. Bloodmeal is nitrogen, oyster shell is calcium, and rock dust gives minerals from pulverized rock. If you’re going to use organic fertilizer…ONLY USE A TINY TINY BIT. like a small pinch per pot. It works by rotting and releasing nutrients, but if you use too much, you can throw your pot media pH out of whack and kill all of your roots. I know this is true, because I’ve seen people do it! So literally less than 1/8tsp per 6″ pot…just a pinch for 4.5” pots.
    • Calcium & pH: This topic is particularly important with paphs and I believe the main reason most people struggle with brown and black rot is related to a calcium deficiency in the plant or from potting media that has become too acidic. You see, many paphs and slipper orchids come from areas of the world that are high in calcium carbonate. They are native to limestone regions and mineral rich soils of mountain ranges, where things like calcium, iron and magnesium are more abundantly available than they are in other habitats. Plants adapted to calcium-rich conditions like this will be adapted to and rely on those conditions (including not-acidic soils) to build robust cell walls, resist pathogens, absorb nutrients, and ultimately grow effectively. Consider adding a small amount of oyster shell to your potting media if you’re using rainwater, RO water, or if your tap water is low in minerals or even slightly acidic (<7pH). if you have a plant that is constantly getting brown or black rot, definitely add oyster shell to your potting media, and understand you may not see the change until the following season when the new growth has been built with the calcium-rich conditions you’ve just provided. Calcium is non-mobile, so cell walls that were made in a deficient state will stay deficient.
      • Where to get oyster shell? Pet stores will carry it in the bird section and you can probably find it online on Amazon in the pet section.
      • Looking for more information on this topic? Read, “Calcicolous Slipper Orchids” by Tony Budrovich

 

Other Paphiopedilum Care Requirements

Generally speaking some other tidbits to be aware of that may influence your success: some species are warm growers, others are cool growers; some require very bright light and grow fast, while others are very slow growers and cannot tolerate bright light. You really need to research each individual species and pursue the ones best fit to your climate and conditions, and then tweak the requirements for each type you grow. All of that said…I grow all of my paphs pretty much the same way—so my opinion is that generally there is some core knowledge that can make you broadly successful with these orchids.

Paph tigrimum – a cold-to-cool growing species
This species can be a challenge to grow if your climate is constantly over 30C

 

Photos of Paphiopedilum

Paph Delophyllum (delenatii x glaucophyllum) with two flowers!
A superb and easy to grow hybrid – highly recommended for new paph growers
Paphiopedilum lowii
Paphiopedium primulinum var. alba
Note: Yes, I know the correct way of writing the alba form of primulinum is NOT to include the “var. alba” because the very first form of this found was the alba variant. However, for breaking and tracking my plants out of bloom, it’s helpful. Why? Well…if you want to cross two alba flowers and have a chance at making alba progeny, both parents need to have that pigment-lacking mutation. It is more helpful to call the plant “var alba” when we know there is a standard form – especially for tracking tags and future breeding projects.:
Some paphiopedilum repotting photos
A nifty (and fragrant) hybrid I have that is unnamed and has rosthchildianum, henryanum and primulinum in its lineage.