The Blue Potato Bush (or Gentian Bush) isn’t exactly known for being “low maintenance,” so it’s no surprise that propagating it takes a bit of effort. But don’t let that discourage you! With a little patience and the right technique, you can successfully grow new plants from seeds or cuttings.
Is growing from seed worth it?
I’ll be honest: growing these from seed can be a bit tricky. The key is consistency—both the temperature and moisture levels need to stay rock-solid during the germination phase. If the seeds dry out even once, your chances of seeing sprouts are pretty much zero.
You’ll want to keep the soil between 72°F and 79°F (22°C to 26°C) at all times. Usually, you’ll see the first little sprouts after four to six weeks, though they like to take their time. Once those first seed leaves appear, you can dial the temperature back slightly to a range of 65°F to 72°F.
Pro tips for seed success:
- Pre-soak your seeds to give them a head start.
- Use a high-quality seed-starting mix.
- Don’t bury them! These are light-germinating seeds, so just press them gently into the surface.
- Keep the soil consistently moist (this is non-negotiable).
- Maintain a steady temperature of 72°F to 79°F.
- Expect a wait time of about 4 to 6 weeks.
- Watch out: Letting the soil dry out just once can ruin the whole batch!
How do I propagate with cuttings?
Growing from cuttings isn’t always a guaranteed win either, so my best advice is to take several cuttings at once to increase your odds. You can even tuck two or three together in a single pot of starter soil.
After a good initial watering, cover the pot with a clear plastic bag or dome to create a mini-greenhouse. Place it in a bright, warm spot, but keep it out of direct sunlight so you don’t “cook” the babies. Keep the soil evenly moist and make sure to lift the cover daily for some fresh air to prevent mold. Once you see new leaves popping up, you’ll know they’ve successfully rooted!
How do I take the perfect cutting?
Look for shoots that are about 4 to 6 inches long. You want “softwood” cuttings—meaning green stems that haven’t turned woody yet—because they root much faster and more reliably. Interestingly, many gardeners recommend choosing stems that already have buds or flowers. There’s a bit of garden lore that says plants grown from non-flowering shoots might struggle to bloom later on.
Quick tip: Keep in mind that even as they grow, these plants stay sensitive to the cold. They definitely cannot handle frost!
