How to successfully grow Iboga from seed.
Tabernanthe iboga is a tropical shrub from tropical western Africa that is used for its hallucinogenic effects from the roots. Being from a very hot and humid environment, people in cooler and/or dryer climates sometimes have difficulty growing this species. One of the more difficult aspects of growing Iboga is the early days of sowing seed sand getting viable plants from them. Here we discuss some methods we have found useful in germinating fresh iboga seed with near 100% germination rates.
What is needed from a seed?
The best possible situation is to buy, or obtain, your seeds from a fresh fruit. If from mail order, it is preferable to order a whole fruit, not separate seeds. This is to ensure the freshest possible seeds as they will not be drying out or in any way harmed while in the fruit. The fruit should be harvested when it has turned orange and is ripe, it may still be firm to avoid mold during long distance transit. When the fruit arrives, we personally find great success leaving it in some almost-dry sphagnum moss until it starts getting soft and even until the very first signs of mold show up. the mold will eventually rot the fruit, but once it has just started getting hold the fruit will be soft and the seeds quite mature. Seeds we have sown have had 95% success rate germinating.
Seeds that cannot be obtained in the fruit but already taken can still be good. It is essential that the person who has removed the seeds places them in slight moisture or extremely high humidity out of light to avoid the seed coat hardening. If seeds are to be removed from the fruit they should be placed in some moist sphagnum moss, vermiculite, perlite etc. to prevent them from drying out. Seeds that are still fresh and dried have out seed coats can still germinate but the % is often lower and also the time it takes may go from weeks to months.
Ideal Environmental Conditions
Tabernanthe iboga is from an extremely tropical region of the earth and thus requires both high heat and humidity to truly do well. The same goes for germinating seeds.
Temperature: 30-35C is the best temperature we have seen for both growing large plant sand sowing seeds. 25-40C is still acceptable but extremes tend to cause more sporadic germination.
Moisture: One of the biggest problems many growers have growing some plants from seed is that they are unintentionally keeping them far too wet causing bacterial and/or fungal attack. With plants like iboga, the seeds are ready and primed to germinate almost instantly, even while still in the fruit. They in fact cannot fully dry or the seed dies and will not germinate. With this in mind we do not necessarily need to send the seed a trigger to germinate, such as soaking or keeping it very moist/wet, like some other plant species. All we must do is simply keep it from drying out and rotting, it will germinate just fine as is like that. Easy right?
Humidity: Humidity seems best around 90%. With high humidity, fresh air should still be available. Many times gardeners will up the humidity at the expense of air flow effectively cutting off fresh air, creating a stagnant environment ripe with pathogens.
Soil Moisture: It should never be wet. How can one tell? if one were to take a handful of the wet soil and squeeze it, just a tiny bit of water should drip out. Wet soils are restricted to air flow and no gas movement under the soil is as important as above the soil.
Light: Before the seeds germinate, light is not needed. Iboga is not a species that requires light to help germinate. It is ready to go right away. Once the seed germinates and a seedling pokes up, fluorescent lighting is well suited. More below.
Sphagnum moss: Our preferred method of germination is using sphagnum moss, as is typical for most of our tropical species that are sensitive and difficult to grow from seed. It is incredibly important to have new and clean sphagnum moss that has already been dried. If mold problems are an issue in your area, take this warning very serious as moldy moss can take over seeds in a day. Also avoid moss with lots of non-moss particle like grass or twigs, these easily contaminate with mold.
Step 1: Prepare your seed germination container. We like glass jars of about 150ml or so. Plastic containers or bags also work well but we have noted amongst numerous tropical species germinated in bags that contamination is far higher when seeds touch the plastic edges, and thus we found that rigid open topped containers make it far easier to control the placement of seeds.
Take you clean sphagnum moss and soak it entirely in clean room temperature water. Make sure it all gets in contact with water. Take the moss with your hands, leaving few to no little strands hanging outside your grip, and squeeze fairly hard removing most all of the water. This makes the moss entirely moist, 100% humid and NOT wet. When using a small jar/cup, fill the bottom with a 1-2cm layer of moistened moss.
Step 2: Clean your seeds well to prevent mold in the future. Generally speaking iboga is OK at handling mold, not ultra-resistant but not too easily bullied around by it either. However one thing that promotes pathogen attack on seeds is excess sugars, which is what is inside the fruit. Iboga seeds will be wrapped in a thin skin like membrane, which when removed reveals all the cracks and crevices in the seed coat. We want the seed to be like this and rinsed with clean, not cold, water to remove any extra pulp and juices.
Step 3: Place the seeds on top of the layer of moss in the bottom of the jar. It is best to keep them separated in case one rots it will not instantly contaminate the rest. We like to plant in groups of 5, dice pattern, in a roughly 7cm diameter jar.
Step 4: More seeds can be added by placing a 2cm thick layer of more moistened moss between each layer of seeds. Note it can be tricky, once germinated, to untangle the roots from the moss and each other. Consider this when planting with density in mind.
Step 5: When all the seeds are placed into the moss we suggest a thick top layer in order to help prevent rapid evaporation of water from the moss and a subsequent dehydration of the seeds/sprouts. We often fill the jar, using 3-4cm. Depending on your local environment, the lid can be placed on with holes or left off. If you live in very humid region, 85% +, you may be able to get away with the jar lid off but great attention must be paid to make sure the jars do not dry out. Truth be told we have forgotten many an iboga jar, and still had some pull through just fine with up to 6 days dry. Let's try not to test the limits though.
Step 6: Within hopefully as soon a week, or as long as months, a little white root will emerge. Good sign things are correct. The root will continue downward, this creates problems when using small bags as the roots get really tangled. Jars that have shallow layers of moss under the seeds will also get J rooted and all mixed up. This can be avoided by using deeper containers or using this sphagnum moss technique on top of a soil filled pot instead of a jar.
Step 7: When the plants start to germinate and the root is about 1-2cm long, we decide to pot them up. Use a well-drained medium with little organic matter to start, just to prevent pathogens/pests. Plant the seed with the root facing down into a small hole made in the soil. 4cm pots are ideal. Do not bury the seed! Place the root down into the soil with the seed level with the soil line and top dress with the same moistened sphagnum moss you germinated the seeds in. This prevents the seed coat from drying and also the soil.
Step 8: The plant will sprout up through the moss with the seed still attached, and here is perhaps the last great hurdle of Iboga from seed. The seed coat does not easily separate and comes off in small chunks usually, rather than splitting in half and falling. Many times, the seed coat pokes above ground to dry air, dries, and then strangles the stem and the plant cannot emerge and dies.
Step 9: The seed coat can be removed manually, very carefully! but this is very risky and good eyes and steady hands are required. To try and avoid this situation, raise humidity in the environment, without sacrificing light and air quality. We opt for simply using pots filled half full of soil and planting them like that. The moss we keep raising up with the seed coat in order to surround it without blocking it from rising upwards. This will help keep in humidity in the region of the seed coat, helping greatly to avoid death by seed coat strangulation.
Step 10: If all went well, the seed coats is off and the leaves are out, job well done. Keep plants in warm, 25-35C, 40-70% shade with 80%+ humidity. The plants can be slow growers, and once they get established can be fertilized somewhat frequently. They like well drained and rich soils once they have a strong stem and root system.