Tutorial: How to Grow Orchids from Seed (Flasking Dry Seeds & Green Pods)

In Breeding, Flasking & Invitro Propagation
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This article covers how to breed and grow orchids from seed at home and while the examples used are Phalaenopsis orchids, I’ve used this exact same method for other types like Phragmipedium and Ludisia jewel orchids. Orchids are unlike other plants and are not easily grown from seed. That is because the seeds are microscopic and lack an endosperm (the nutrient pack that feeds the embryo in “regular plant” seeds). In nature, orchids have established a symbiotic relationship with fungi, and they rely on that fungus to feed the seedling during early development.

When growing orchids from seed at home, it’s a hassle to try and grow the correct fungus species for the specific orchid (which can vary by species); instead, we remove the fungi from the process and provide the nutrients the embryo needs (along with ideal conditions for the tiny orchid embryos). We do this “invitro” or “in flask” which means the nutrient media and seeds must be 100% free of fungi and bacteria contaminants—not doing so could mean runaway growth of infection overtakes and kills the seedlings.

Reading between the lines, you have probably guessed that growing orchids from seed is an involved process. It’s also long—taking about 1-2 years of in-flask growth before you have seedlings you can grow exvitro (out of flask). However, a single seed pod can potentially yield hundreds or thousands of plants, and making your own hybrid opens the doors of creating something brand new—a new plant never seen before on this planet—so it is also rewarding and fun (if you’re into this sort of thing).

My background: I flasked my first orchid seeds on November 7th, 2018, and currently have a few dozen types of orchids growing invitro. Orchids I’ve flasked include phalaenopsis, phragmipediums, paphiopedilums, and jewel orchids (Ludisia discolor). I once flasked Ophrys apifera (a rare European terrestrial species), but it turns out terrestrial orchids need a different nutrient media and the few seedlings that germinated, later died. How we succeed when growing orchids from seed, comes down to sharing experience, and unfortunately, when I first started growing orchids from seed, it was a struggle to find well-documented or detailed information about the process. Unfortunately, there just isn’t a lot of info online about the process of growing orchids from seed. I’ve created this article to share what I’ve learned, help others take the first step, and answer questions for those who are curious about growing orchids from seed.

A couple notes before you get into the depths of this article:

  1. I update this post periodically, so check back on occasion.
  2. To complement this post, I’ve created a short series of orchid flasking videos on YouTube, so you can see exactly how I sow seeds myself.
  3. I’ve also launched the “Orchids from Seed” Facebook community—join us if you’re passionate about discussing and learning how to grow orchids from seed.

Before getting started: If you’re really keen to grow orchids from seed, I encourage you first to try buying a few orchid seedling flasks and raising those plants that someone has already done the hard work with. Growing orchids from seed takes about 8-24 months in flask, and then you’re looking at another year or more to get them to flower after you deflask. If you don’t have experience deflasking and growing baby orchids, you may find it very frustrating to have spent over a year growing them invitro, only to have them die when you finally deflask them. There are typically vendors who sell orchid flasks and it’s a great way to get that experience beforehand. Then you’re more likely to be successful when your own seedlings are finally ready to be deflasked. If you want tips on deflasking orchid seedlings, I’ve covered everything I believe to be valuable in this post and if you want the grueling details, I also tracked my first deflasking in this post from back in September 2017. So with the intro and background out of the way, let’s get into the details.


Growing Orchids From Seeds – Sections of this Article

Video Slideshow: a quick flasking outlined later in this article

Background Topics of Interest When Growing Orchids From Seed

Why do you need to flask orchid seeds? Why can’t we just plant them in a pot? They grow fine in the wild…right?

Answer: You need to grow orchids in a flask because orchid seeds don’t have the nutrient packs that other plants have to sustain the embryo. In nature, orchids form a symbiotic relationship with fungi called, mycorrhizae, which IS NOT the same fungus as a “mushroom”)—and through this relationship, the fungi provides sugar and necessary nutrients for the orchid…and even if there may be no (or very low) light for the orchid to photosynthesize, the fungus helps it grow and become a plant large enough to reach the light (at which point it will be capable of sustaining it’s own life through photosynthesis).

Orchid Seedling Development: Biology & Nature

In the wild an orchid will produce thousands of seeds from just one seed pod. The seeds are so light, they carry on a breeze and are dispersed everywhere: on leaves, on branches, on tree trunks, on moss, on exposed rocks, and of course on the ground. Then the rains come and they wash the seed down into the crevasses and nooks, through cracks in the bark, through the faults of rocks, and into the moss – there, the seeds end up in dark and damp ideal place where both fungi thrive and where a tiny baby orchid will not dry out. The majority of orchid seeds do not make it past the germination stage because they don’t land in the right place, which is why the plants produce so many seeds.

Unlike the seeds of regular plants, orchid seeds lack any form of nutrient storage. If you think of a pea or bean – the two chunky halves inside the skin…those are not the embryo itself but are in fact food for the embryo. Because orchids lack that nutrient reserve, they depend on fungi to survive.

Important Considerations & Roadblocks When Breeding Orchids

When breeding orchids, you will come up against challenges and considerations, so these are some important topics to work out early on.

BE DILIGENT: Label Everything

Do you know what’s a pain? Labeling everything. Do you know what’s even more of a pain? Having a flower bloom 3 years later only to find out it was labeled incorrectly and now don’t know the original parents and have a “NOID”—I cannot count the number of times I’ve bought seedlings from vendors, only to bloom them years later and find out they were mistagged. It’s bad for business and it’s bad for your brand. Another example, You’re flasking your seeds and working on multiple seed pods at a time, then you get the flasks mixed up and now you don’t know which flask is which.

You’re investing years of your time into this. Take the extra effort to be diligent and label the seed pods, the flasks, and the plants as you progress through each stage. Starting a spreadsheet to track your hybrids is good practice too. Record your attempts, the dates, the crosses, the media, the more info you track, the more you’ll know in the future about your successes and failures. Having a notebook is a good idea too so you can jot down notes as you’re flasking or working with your plants. I am terrible for thinking “I’ll remember this later” and then I forget the important details! Don’t be a Dustin.

Struggles of getting viable seed: Sterile plants, Difficult breeders, & Seed Infertility

When breeding orchids, something you should beware of is the relatively high occurrence of failure before seed is even produced. I would say of all the hybrids I’ve tried to make with my phals, I’ve only had about 8% success for pod creation—that’s about 1 seedpod for every 13 attempted pollinations (26 flowers burnt for one pod)! I work mostly with hybrids, where this can be more common (compared to working with species). But here’s what you should know: the ploidy (gene pairing), gene count, and gene size of plants affects their ability to produce seed, which becomes a possible issue when working with hybrids more than it does when working species only. Odd chromosome numbers (or “aneuploid” plants) and other oddities like triploid (3-chromosome pairs) plants may be more difficult to breed or be fully sterile, producing no seeds or no embryos. This area of breeding is where it gets quite complicated and will require more research for you as you get further into growing orchids from seed. If you’re new to all of this, that’s totally okay, just understand that you may experience high failure and make relatively few seed pods as a result of plant genetics and chromosomes.

Should you breed hybrids or species orchids?

This is personal preference, and it will depend on your personal goals. Do you want to make new hybrids and improve old ones? Or would you rather work only with species orchids, ensuring they have a future lineage? You can always do both, but it’s a consideration non-the-less.

Understand the difference between “sterilized” vs “disinfected”

  • Sterilized means there is no chance pathogens survived–heat is the way to sterilize.
  • Disinfection is done using chemicals or soap in an attempt to kill pathogens…but sometimes they can survive.
  • You sterilize the media and cutting tools by heating them, you disinfect the seeds, your gloves, and working space by using chemicals like chlorine, hydrogen peroxide or rubbing alcohol. It’s important to understand this distinction because it will help you see where potential contamination will happen—and trust me, you will get contamination when you first start out.

Cleanliness is next to Godliness: Keep your workspace clean, your tools sterilized and your seeds and seedpods disinfected

This was a challenge for me personally because there are so many vectors to consider when you’re experiencing flask contamination. You must keep your workspace as clean as possible and turn any fans or in-room airflow off to prevent spores blowing into your workspace as you’re working. A single spore, yeast or bacterial cell (which is ALLLLL over your skin) can destroy all of your hard work. Treat yourself as the primary vector for contamination—your breath, your skin, your nails, they all have microbes— so you have to be extremely careful when moving things around. Move slowly and deliberately to prevent a lot of air movement. Work expediently and reduce the amount of time a flask is open. And of course wash your hands constantly. You’ll likely still get contamination, but how well you attend to this early on will determine how much success you experience.

A note on sterilization: Heat is the #1 way to guarantee pathogen destruction. 121•C is the target temperature required to kill all pathogens and spores (for 15 minutes). 121•C is achieved by reaching 15PSI on your pressure cooker or autoclave. People have had success with lower temps and/or microwave sterilization, but if you want to guarantee that your flasks and tools are clean, you’ve got to hit that temperature for 15 mins. Fire (open flame) is the other way to kill viruses, bacteria and fungus on your tools.

Viruses start from the first cut of a seed pod – Flame all tools before use

Viruses are a different monster than bacterial and fungal infections. You don’t see them, they likely won’t show up in flask, and they can be transmitted to your seedlings simply by re-using a scalpel used to cut infected plant tissue. This means you can’t go slicing and dicing without flaming that blade between cuts. Why do you think viruses in orchids are so prevalent? It’s because with tissue culture and stem propagation it’s easy to cross contaminate if you don’t have absolutely stringent sterilization techniques. A single unflamed scalpel can transfer a virus from one plant to all of your plants…including the clones. Same goes for seedlings – so be diligent.


Getting Started with Breeding: Timeline

Before we get into the processes of orchid breeding, I’d like to instill in your mind what type of commitment you’re making…

How long does it take for an orchid to go from flower, to seed, to flask, to a new flowering orchid?

The short answer is: A minimum of about 2.5 years; an average of 3-4 years; but up to 15 years in the case of some slow-growing Paphiopedilums. From seed to plant (and what’s in between – PLB protocorm like bodies), orchids go through 5 phases as they transition from an embryo to a “regular plant”; those stages and timelines are generally as follows; but just be aware the timelines will vary by species, temperature, light and other conditions unique to your home:

  1. [~80-250 days] Pollination & Seed Pod Maturation
  2. [2-3 weeks] Seed Sowing into Mother Flask, swelling of embryo, & “greening” of first PLBs
  3. [~3 months] Protocorm-Like Body (PLB) which is a green blob of tissue
    1. [~4 weeks] Small PLB (into spreading flask – if too many)
    2. [~6 weeks] Medium PLB (can be omitted if there aren’t too many seedlings)
    3. [~2 weeks] Large PLB (into first replate)
  4. [~12th week] Differentiation – where the PLB establishes “up” vs “down” and roots and leaves begin
  5. [6-15 months] Vegetative Stage (into final replate)
  6. Transitional Stage (deflask)
Image of Orchid Development Stages in flask


Understanding what you’re getting into, if you’re still on board, let’s talk about orchid sex…


Pollinating an Orchid Flower

Before we skip right into pollination, there’s a quick lesson you need with regards to orchid pollen:

Orchid Pollinia

Unlike standard plants that have “powdery pollen”, orchids have cohesive masses of pollen known as pollinia. The pollinia is often hidden and many orchid have evolved specialized pollinators. Generally, the pollinia is stuck to a bug (the pollinator) with a sticky adhesive. Then the pollinator carries the pollen mass the next flower and pollination is achieved.


How to Pollinate a Phalaenopsis Orchid flower

Pollination Tools
  • Toothpick
  • Water – a very small amount works – in a shot glass
  • 2 flowers – one for pollinating, one for pollen
How to Pollinate an Orchid
Steps to Pollenating a Phalaenopsis Flower
  1. Grab a new toothpick
  2. Carefully pull the anther cap off the pollen parent and drop it onto a piece of paper or plate
  3. Carefully pull the cap off of the pollen – this is harder than it looks, and I frequently lose pollen that goes flinging off into the air
  4. Once the pollen is free from any stickies or bio mass, you want to transfer it to the female section of the flower
    *this must be done quickly or you risk dropping the pollen if the water dries:
  5. Dip toothpick into water (about 1/4″)
  6. With a light coating of water on the tooth pick, move it over a single pollen packet, and make light contact; the water tension should grab the pollinia
  7. Move diligently to the flower, and using your free hand, invert the flower upside down
  8. Position pollen into the flower and put the pollinia near the back of the flower – put slight amount of pressure to ensure it sticks to the sugary goop
  9. Slowly release flower to regular position
  10. Wait 24-48h and watch for the reception site to close over the pollen
  11. If the flower closes, and the pollen is accepted, the flower will begin to turn green or whither and the ovary will elongate. If the ovary dies, the pollination has not been accepted.


Photos of Successful vs. Failed Pollenations
Pollinated Flower Starting a Seed Pod


Failed phalaenopsis pollination attempts

Questions Regarding Flower Pollination

When is the best time to pollinate a flower?

I have found about 4-7 days after the flower has opened. Ideally you want the flower to be fully open and just starting to emit fragrance (if it’s the fragrant type). Older flowers may have variable outcomes for seed production (for both pollen and receptivity)

Should you use pollen from a flower you plan on pollinating (swap pollen for example)?

You can, I have, and I got a seed pod from the plant…that said, upon further reflection, it may be better to NOT use pollen from the exact flower you’re intending to pollinate. In some plants the flower will fade sooner after pollen has been removed, as short as 48 hours after. You probably want to give the plant maximum amount of time to complete the pollination attempt.

Can I split or divide pollinia to fertilize more flowers from one flower? 

Yes; flame the blade of your scalpel before and after you cut the pollinia; personally, I’d rather pack more pollen in, in an attempt to get the most possible viable embryos and then sow less seed if you have an abundance. I have had crosses produce very little seed and splitting the pollen would have only lead to even less seed.

Can I use multiple pollinia in a single flower?

Yes; but only do so if they’re from the same parent. You don’t want a mix bag of babies. It’s typically only good to do so if the pollinia is exceptionally small, for example from Phal equestris, deliciosa, or mirabilis.

How long does it take a pollinated orchid flower mature into a seed pod?

Once a flower has been pollinated, you’re looking at about a minimum of 1 month (30 days) up to 14 months for that pod to mature and split with viable seed. Green pod and dry seed maturation times will vary based on the species. For example, Ludisia discolor (and other jewel orchids) can produce dry seed rapidly (within 30-40 days), while Phragmipedium take a bit longer (about 3-5 months). Phalaenopsis seed pods take about 6-8 months to mature. Paphiopedilum seed pod maturation times vary greatly (with Paph lowii taking only 5 months, while Paph tigrinum takes up to about 14 months).

There is a document on green pod maturation times on the AOS website. But again, keep in mind individual species (and hybrids) will vary. A strategy used by some is to pollinate two flowers offset by 1 week. Then the first pollinated flower splits and you know when to use the second seed pod. I just watch the seed pod color closely and as soon as the color tint starts to change, I know dehiscence (splitting of the pod) will happen within a few days.


The Orchid Seed Pod

As the orchid seed pod forms, the ovary will swell as the embryos grow. The pod is full of chaff a white course, but fluffy looking material that helps push seed out of the pod once it’s ripe. Seeds nearest the column (where the flower was) will have a higher likelihood of being viable as the pathway from pollen to the eggs flow from the flower toward the stem. The image below (taken and observed by Allan Black) illustrates how the coloured seed hold embryos while the white seeds are sterile and have no viable embryo.

Photo of Orchid Seed Capsule
By Allan Black (Hobby Orchid Grower & Breeder)

Allan Reports:

Initially, I assumed the tan seed was either contaminated or some of the alcohol that I was using to sterilize the capsule had leaked into the seed (causing it to discolor to tan). I initially flasked the white seed thinking that it may be less likely to be contaminated or damaged. Later, I look at both color of seeds under a microscope and discovered that the white seed did not contain any plant embryos and that the tan seed contain lots of embryos. I re-sowed the flasks with the tan seed.—Allan Black


Deciding the right method: Dry Seed vs. Green Pod

When it comes to sowing orchid seeds, you have two options: dry seed or green pod. A green pod means the pod is…still…green; and therefore the seeds are tightly bound within and still maturing. The thing about a green pod is, while the seeds are still maturing, you can flask them after about the half-way point to the seed pod’s maturity. Dry seed, the other method, is when the seed pod has split and the seeds are exposed to air…this means the seeds themselves are potentially contaminated with microbes. Most people opt for the green pod method because there is the perception of fewer risks of contamination; however there are benefits and drawbacks to each method and I prefer sowing dry seed.


Why Flask Dry Orchid Seed

Advantages to Dry Seed Sowing
  • Long-term Storage & Future Practice; seeds can be stored for many years (though most report that viability declines quickly after pod “pops”) giving you a chance to try and try again if your first attempts fail.
  • Mature Seed; seeds are guaranteed to be mature (assuming the embryos are viable)
  • Easier; you put the seeds into a syringe and disinfect – then you blot a bit in each flask. For me this is easier than dealing with the green pod.
Disadvantages of Dry Orchid Seed Sowing
  • Greater risk of contamination b/c seeds are exposed to air before going to the media
  • Pod time (longer); takes on average 50-100% longer time to create a fully-ripe seed pod
  • Disinfecting process can kill seeds; if solution is too toxic, it kills the seed; if solution is not concentrated enough, pathogens invade.

Why Flask Green Pod

Advantages to Green Pod Orchid Seed Sowing
  • Lower risk of contamination; seeds are not exposed to bacteria or fungi provided the pod does not rupture and proper sterilization of the pod has taken place
  • Shorter maturation period; around 120 days vs. 220 for phals for example
Disadvantages to Green Pod Orchid Seed Sowing
  • One shot, no retries; if you have a contamination issue, if you drop the seedpod, if your sterilization solution gets into the pod, or your media is bad, you’re whole attempted is done.
  • Seeds may not be mature enough; some seeds take longer to mature and it depends on the species, not just the genera of orchid.
  • More “hands on”; if you’re working in a glove box, trying to fumble with and cut an orchid seed pod through foggy vision is incredibly difficult – to make matters worse, bleach makes the seed pod quite slippery so while it is supposed to be an easier method, I found it much more cumbersome than dry seed flasking.


Is it better to flask dry orchid seed, or a green pod?

Answer: That is entirely up to you. I tried both methods and I prefer dry seed because I find it much easier to get the seeds into the flask. For you, the aspect of green pod may be more enticing because it has less chance for pathogens and is therefore overall more reliable for getting seedlings.

Here’s a video where I cover my justification for doing both dry seed and green pod: 


Checklist: What you will need to sow orchid seeds invitro

  • Orchid seed (a green pod or dry orchid seed)
  • Flasks and/or Vials
  • Orchid Seedling Media (Either Phytotech P668 – Orchid Maintenance Media with Charcoal or Sigma 6668 Orchid Maintenance Media)
  • A weigh scale that measures 0 – ~500g (I got one off Amazon for $20 CDN)
  • A contaminant-free workspace: either a glove box or a laminar flow hood (for those who have ample space).
    You can make a glove box yourself – I followed these instructions to get me started. I would recommend getting a container with a gasket – the weather-tight storage boxes should be better for this.
  • A pressure cooker or autoclave (for those with loads of spare cash)
    • Note: The pressure cooker MUST go to 15PSI – At 15PSI, the temp is 121C – which will kill all bacteria and spores.
    • Beware: at 10PSI, you will risk contamination; that means you cannot use those fancy electric pressure cooker like your “Instant Pot”…PS: I tried this, it resulted in contamination. 
  • Chemicals for disinfecting your workspace & tools: chlorine or isopropyl alcohol
    • Household Concentrated Bleach (Sodium hypochlorite): 10:2 (assuming bleach is 8.25% chlorine, this should be ~1.5% chlorine)
    • Isopropyl Alcohol 70% – be careful if you’re using flames to sterilize tools
  • Chemicals for disinfecting Green Seed Pods:
    • Concentrated household bleach: 10:2 (assuming bleach is 8.25% chlorine, this should be ~1.5% chlorine)
  • Chemicals for disinfecting Dry Seeds: either chlorine or hydrogen peroxide
    • Pool Bleach (Calcium hypoclorite, Ca(ClO)2) or Household Bleach (Sodium hypochlorite, NaClO)
      *For disinfecting your seeds: target .1–.5% chlorine
      **Reportedly Household bleach (NaClO) is more toxic to some seedlings than pool bleach (Ca(ClO)2); I have yet to explore the pool bleach, but it’s commonly referred to in other flasking books.
    • Hydrogen Peroxide 3%
      *Use either bleach for disinfecting seed OR hydrogen peroxide…not both
  • Small amount of dish soap (works as a surfactant and ensures bleach/peroxide makes contact with the seed surface).
  • Syringes/plungers for seed sterilization (dry seed only)
  • Tools for cutting: scalpel/sharp knife (green pod only)
  • Tools for manipulating seeds: spoon, dental pick, or other small metal tools


Step 1: Sowing Orchid Seeds (Flask 1 of 3)

Mother Flask – Recipe & Making Orchid Flask Media

Mother Flask Ingredients

  • 13.5 – 15g/L P668 – Phytotech Orchid Maintenance Media with Charcoal
    *I misread a recipe for replates and once used 19g – oops, but it was fine.
  • 5g/L Sugar
    *I use coconut water – 5 g of sugar means 1/4 of a can that has 20g of total sugar
  • 3-5g/L Gelling Agent
    *I used agar w/ a gel strength of 1.5% – 6g was not enough; 7.5-8 would have been better.
  • 1L Distilled Water
    *I use bottled Aquafina which is distilled water; I checked the pH of Aquafina a few months later and discovered that the pH is ~4 and since I have started adding ~30% tap water when making any orchid flask media

Note: this recipe makes a lot of flasks…probably around 15-20. If you’re just getting started, you might want to consider halfing the recipe, especially if you’re only doing one or two pods

Instructions – How to Make Mother Orchid Media for Sowing Seeds:

Add agar to a small dish of cold water—this will make the process of dissolving it much easier. Bring water, sugar and gelling agent / agar-water to a rolling boil and turn off heat.

Pour 1/8-1/4” of media in each flask, put lid on top and put into the pressure cooker for sterilizing. Pressure cook at 15PSI for 15 minutes – up to 20 minutes.

Turn off pressure cooker and leave flasks in the pressure cooker until time to flask—if you try to rapidly cool the pressure cooker (in the sink with cold water), or if you open the seal too soon, you’ll risk contamination as the air rushing in to the pressure cooker brings pathogens.

Photo of Dry Phalaenopsis Seed Pod & Syringe 


Steps to sowing seed in mother flask (Flasking 1 of 3)

  1. Make a glovebox or purchase a laminar flow hood in order to work in a sterile environment.
  2. Prepare the orchid seedling agar media, pour media into the flasks, and sterilize at 15PSI for 15-20 mins.
  3. Allow media to cool for 24 hours (by leaving the pressure cooker and all contents undisturbed until completely cooled); this will reduce contamination because the air in the vials will also be cool and therefor won’t suck in a bunch of contaminated air.
  4. Move tools and sterilized orchid flasks into the glove box / working area.
  5. Spray all items with 20% bleach solution to sterilize the inside of the box; wait 15-20 minutes
  6. Spray again, and then proceed with work
  7. Sterilize seed or seed pod
    • Dry Seed Instructions
      Video: Sowing Dry Orchid Seeds
      Tip: If you notice the pod yellowing, get a letter envelope and put it around the pod; the pod will split from the bottom, and the seeds will start to fall down – you’ll want to catch those (but keep them separate from the pod seeds, as there’s a higher chance these will be contaminated).

      • Disinfect Seeds using 3% peroxide
      • Alternatively, you can use bleach (Sodium chloride) – Goal: .1-.5% active chlorine; or
      • Pool chlorine (Calcium chloride) – Goal: .1-.5% active chlorine
        * But I have not had success with either chlorine method
    • Green Pod Instructions
      Video: Sowing Green Pod Orchid Seeds

      • Using bleach (Sodium chloride) – Goal concentration: .8-1.5% active chlorine
  8. For each flask:
    1. Open the lid
    2. Transfer disinfected seeds into the flask
    3. Place lid on flask and tighten the lid so it’s secured
    4. Proceed to next flask
  9. When all orchid seeds have been flasked
    1. Take the flasks out out one-by-one and place a one-inch strip of saran wrap around the top of the lid (covering the sides of the flask which will help prevent pathogens from getting in) and tape shut with the label or elastic band.
      *Some orchid breeders use a larger single piece of tin foil and wrap it over the entire lid. I don’t like this because it blocks light from the top-down.
    2. Make sure you label each flask
  10. Place flasks near indirect light specifically avoiding any direct sun which may overheat the seedlings; bright LED grow lights work very well.
  11. Wait 4 weeks (or longer) until you see protocorm like bodies (PLB)
  12. Move to a brighter location, still avoiding direct sun
  13. If after 4 weeks the PLBs are mounding heavily, replate them into a “spread” of this same media recipe but in new flasks (simply spreading the seedlings out so they all get access to light);
  14. Wait 4-12 weeks until the PLBs swell heavily and start to differentiate (go from PLBs to plants w/ leaves);
  15. Replate plants into new flasks as they get too large for their current flask.


[Immediately After Flasking]
Photos Sown Orchid Seedlings


[After 14-21 days]
Photos of the Flasked Orchid Seedlings
White bacterial contamination 🙁 – Phalaenopsis protocorms in flask
Contamination-free test tube with phal seedling protocorms

After you’ve sown orchid seeds – caring for flasks

I honestly didn’t think this would be a thing I’d have to worry about. I figured that flasking would be the bulk of the effort, but as you can see, I started to get contamination in the large flasks after about 2-3 weeks. All of the little test tubes were contamination free while the big flasks all eventually got contaminated. After a bit of research here’s what I discovered:

Temperature Changes & Flask Types – Flask Contamination

I live in Canada. In the winter, the indoor temps can swing from about 25C on warm days, down to 15C (lowest) on cool days. That 10C difference can cause an expansion and contraction in the air within the flask creating air draw which may pull in contamination. When I started breeding orchids, I was using those square flasks that don’t have threading and they had an EXTREMELY high rate of contamination in my conditions (literally 100%). I messed around trying to regulate my temps but in the end found the best solution to variable temps was to use threaded flasks. I have used: spice bottles, babyfood jars, and mason jars with plastic lids purchased at Walmart. All of these options have worked much better than the square flasks.


Spreading: Taking PLBS from one mother flask into new mother flask
(Optional, but best done if seedling density is high)

This is a step is only required if your protocorms are piling all over one another. What will happen if you don’t is the seedlings under the top layer will eventually die. Spreading them into a new mother flask allows both flasks the opportunity to feed ALL the seedlings. It’s always a risk for introducing contamination, so ideally you want to sow less seeds and avoid this step if possible.

Steps for Spreading Orchid Protocorm-like Bodies

Take the mother flask and a second un-sown flask with mother media and put them into the glovebox. disinfect your work area and outside of both flasks. Use a tool (spatula or whatever) to scoop PLBs from one flask into the second. Do your best not to touch anything other than the media or PLBs. Spread them in the new flask and redistribute the PLBs in the old flask. Your goal is to end up with two mother flask.

Photos of Spreading Orchid Protocorm-like Bodies


Light / No Light

Some species of orchids need darkness to germinate. Typically this applies to terrestrial species; however, I have had no problems germinating Phalaenopsis and Phragmipedium seeds by putting the flasks under lights immediately after sowing (and NOT doing a “darkness treatment”).


Step 2: Replating Orchid Seedlings (Flasking 2 of 3)

Transferring Seedlings Protocorms to New Flask

Replate Flask Ingredients (for Protocorm Like Bodies (PLB) Transplant)

  • 20g/L P668 – Phytotech Orchid Maintenance Media with Charcoal
  • 5g/L Sugar
  • 25g/L Banana *better if lightly green
  • 50g/L Potato – cooked (can be microwaved) then mashed
  • 3-5g/L Gelling Agent (or 8g agar)
  • 950ml/L Distilled Water

Instructions – How to Make Orchid Replate Media: Blend Potato and Banana with some distilled water. Like with the mother flask, add the agar to cold water, then mix all ingredients together. Check the pH – ideally the pH should be around 5.5-5.8.  The P668 media is usually adjusted, but adding banana and potato can alter the desired pH. Adjust the pH if needed (citric acid for more acidity, baking soda to increase alkalinity). Once that is done bring the mix to boil. Then fill the flasks (1/4” deep) and autoclaved.

Replating From Mother Flask to New Replate Media


Replating Instructions

At the most basic level, your goal here is simple: move the green blobs from one flask to the next without introducing contamination. As you replate them you want to give the seedlings space in the new flask to give them room to grow. The video above will walk you through the details of the replating process; but to get started make sure you have these items ready and your workspace setup:

  1. A small dish of peroxide (3%) with less than a drop of dish soap
  2. A small dish of bleach (25%)
  3. A spray bottle with bleach (20%)
  4. Tweasers and/or metal tools that have been sterilized with fire before starting work.

Replate Process: Place mother flasks and new flasks into the glovebox. Spray the outside of all flasks and tools with the bleach solution (20% bleach, water, & a drop of dish soap). This step is important for preventing contamination of both your replates and your mother flask, so be diligent and liberally spray the flasks paying special attention to the lid and rim. Let everything sit wet with the bleach water for 10 mins, the proceed with transferring the protocorms to the replate media.

For best results: after each tool is used for a replate, put it into the bleach solution for 30 seconds, then transfer it to the peroxide solution to rinse off the bleach. Then proceed with the next replate. Once all the replates are completed, leave them under lights for the next 12 hours which will neutralize any peroxide. As an aside: the purpose of the peroxide in this case isn’t for sterilization, but it ensure that you’re able to rinse the bleach off without re-infecting the tool if you were to use a bowl of water.


Step 3: Final Replate (Flasking 3 of 3)

If you’ve made it to this point, the final replate is pretty straight forward. Repeat steps for the previous replate except you can use a more nutrient-rich media. Personally, because I’m doing this for hobby interest and not running a large production facility, I have gotten away with just replating into the same media used for the first replate as the final.

Orchid Protocorm-Like Bodies (PLBs) – When, Why, How

Final Replate Flask Ingredients (for Protocorm Like Bodies (PLB) Transplant)

  • 25g/L P668 – Phytotech Orchid Maintenance Media with Charcoal
  • 5g/L Sugar
  • 25g/L Banana *better if lightly green
  • 75g/L Potato – cooked (can be microwaved) then mashed
  • 3-5g/L Gelling Agent (or 8g agar)
  • 950ml/L Distilled Water

Instructions – Making Final Orchid Replate: Blend Potato and Banana with some distilled water. Like with the mother flask, add the agar to cold water, then mix all ingredients together. Check the pH – ideally the pH should be around 5.5-5.8.  The P668 media is usually adjusted, but adding banana and potato can alter the desired pH. Adjust the pH if needed (citric acid for more acidity, baking soda to increase alkalinity). Once that is done bring the mix to boil. Then fill the flasks (1/4” deep) and autoclaved.


Deflasking Orchid Seedlings

So you’ve made it this far eh? Congrats, that’s amazing! I have created a dedicated post covering how I deflasking seedlings which you can read here; I had also tracked a timeline of my first deflasking a few years ago which you can follow along in this other article. But to close out this project, here is the video of me deflasking the seedlings used through this tutorial:

Information & Resources for Orchid Breeding, Seed Flasking, & Media


Special Thanks

This post was a culmination of research and advice from orchid friends around the world. I’d like to give a thanks to Adeljean Ho (part owner of Neblina Orchids), Ken Avent (renowned orchid breeder), John Barnes, Pat (from Kingfisher Orchids in Canada), and the groupies over at the International Phalaenopsis Alliance (IPA), including: Robert Bedard, CJ Mack, Ben Belton and others.