I've been growing a Norfolk Island Pine for a few years now, and I've learned quite a bit through trial and error. These trees can be quite adaptable, but they do have some preferences. For soil, I've found a well-draining mix works best, similar to what you might use for cacti or succulents. This prevents root rot, which they're unfortunately prone to if waterlogged.
In terms of watering, I try to keep the soil consistently moist but not overly wet. I usually water mine when the top inch of soil feels dry; this can vary based on your home's humidity and temperature. They appreciate higher humidity levels, so if your indoor air is dry, a humidity tray or occasional misting can make a big difference.
Light-wise, Norfolk Pines love bright, indirect sunlight. Direct sunlight can scorch them, so I keep mine in a spot where it gets plenty of light but no direct rays.
For those who decide to grow these from seed, patience is key. It can take a while for seeds to germinate, and maintaining a stable and warm environment is crucial. I've heard that soaking the seeds overnight before planting can improve germination rates.
Have you tried growing any other conifers? I'm curious how you find they compare in terms of care and growth indoors or in gardens.