Grow Adenium From Seeds
Submerge the seed for 1 to 4 hours in lukewarm, room temperature water. You can use warmer water too, it’s just important that you don’t use boiling hot water. This will make the germination process faster for a day or two. Don’t worry if the seed doesn’t sink. Adenium seed usually floats even after sinking it in water, as opposed to many other seeds.
2. You can use any kind of substrate, as long as the drainage is good. Coconut turf is ideal, just as is cactus soil that you can buy. Standard garden soil can do well at the beginning, but later on and during winter, it may become problematic due to poor drainage.
3. Plastic cups can serve you well as flowerpots during the first few months, and there’s no need for bigger pots. The only important thing is to cut out holes at the bottom. The depth of 1.5-2 inches (4-5 cm) is more than enough for the first few months of growth.
4. First you need to water the substrate, so it can lie down; and then afterwards put the seed HORIZONTALLY on soil and DO NOT PUSH IT. Then cover the seed with a very thin layer of substrate, do not go over 0.2 inches (half a centimeter). Water it again and be careful, as the water stream can move the seed or uncover it. Sprayers will be extremely useful for this task. Feel free to water it, until the water starts flowing from the flowerpot/plastic cup.
5. Leave the flowerpot for a few minutes for the water to drain.
6. Keep the substrate MOIST during germination. You can cover the plastic cup with nylon and tie it with a rubber band, to keep the moisture at a high level. This is THE MOST IMPORTANT STEP for germination as it affects the germination percentage the most. The soil shouldn’t dry until the seed germinates, and it has to be damp (but not completely covered by water). I’ve personally come to the conclusion that the best combination for the germination process consists of cake cover, underneath which I put small pots or plastic cups. In this case, you don’t need to put nylon covers over them, because the cake cover will provide more than enough moisture and air. Another solution may be a plastic fast food box, with a useful cover to keep the moisture. In this case, you can plant your seeds directly in those boxes, provided that each seed is at least 1 to 1.2 inches (2.5 to 3cm) apart.
7. Uncover the nylon every day, so that the fresh air can come in. That nylon-pause should last 10-20 minutes, and then cover it again. If the substrate doesn’t dry off during germination, and is constantly moist, that means that you did a good job. But, if you notice that the substrate is dry on the surface, be sure to spray it a bit, because the seed shouldn’t be in a dry substrate.
8. Your flowerpot has to be on a well-lit place, but UNDER NO CIRCUMSTANCES exposed to direct sunlight, because the seed will overheat in hot soil, and after germination, it will burn out. Ideal temperature is up to 77 to 95°F (25 to 35°C). It’s not a problem if that temperature drops to 62-64°F (17-18 °C) over night, but it’s desirable that it’s over 77°F (25°C) during the day. The seed will germinate even in a room of 70-71°F (21-22 °C) but that will extend the germination time, and probably decrease germination success rate.
9. The largest number of seeds will germinate between days 3 and 5, if you’ve provided optimal conditions. If there wasn’t enough moist or the temperature didn’t go over 77°F (25°C), germination will last longer. It shouldn’t last longer than 10 days. There are examples when the seed has germinated even after a few months, but that doesn’t happen very often.
10. When the seed germinates, you can leave the nylon cover for a couple more days. Feel free to take it off later on, and don’t cover the seed afterwards.
11. When the seed germinates, it will usually dispose of the seed shell on the leaves on its own, but it’s stuck sometimes, and the leaves can’t open. If it doesn’t fall off in 2-3 days, feel free to GENTLY remove it, otherwise the seedling may die off. This can be done easily by spraying the plant first, so that the shell softens, and then gently, with your nail, push the shell FROM THE BOTTOM, and it will easily slide off. If you pull the shell from the upside, you can easily break the leaves. Even if you do this, don’t throw away the plant; instead give it a chance to create some new ones.
12. During the first 2-3 months after germination, the seedlings need to be under a strong light and on a warm spot, up to 100°F (38°C), but under no circumstances should you expose them to direct sunlight. Only after 2-3 months you can slowly let your plant get used to the sun, but first expose it for an hour or two early in the morning or late in the evening, when the sunlight is not too strong.