According to everything I have read about these seeds, they are notoriously difficult to grow. You are right, they are expensive, so I looked at everything available and heres what I gleaned:

1. Boswellia sacra seeds are best to germinate in the spring, however, within a controlled environment, they will germinate any time of year.

2. To germinate the seeds, it is best to use a well-drained soil and set the seeds on top of the soil with some fine top dressing material, like pumice, to cover the seeds.

3. The soil must be kept moist all the time until the seeds germinate.

4. The key to successfully germinating sacra seed is high humidity and high temperature (90 degrees and higher).

5. The difficulty of germination directly reflects the rarity of seed grown plants.

In my opinion, I would try half now and half in the spring. Not knowing what climate you live in, its difficult to know when is best for you to try and raise the seeds.

Oh and dont forget, unless you intend to bonsai the resulting trees can grow up to 25ft tall.

Hope this helps, tell us how you get on, I would be fascinated to know.

I would germinate the seeds as follows:

1. Get some thick white paper towels, such as Bounty, and a large freezer Ziploc baggie.

2. Buy a seed germination heating pad at your hardware store or online at a gardening supply store so your germination temperature will stay at the optimum level constantly.

3. Get some charcoal-filtered water or bottled water for moistening the paper towels.

4. Fold the paper towel in half and moisten with water. Fully wet the towel but do not soak it to the dripping point.

5. Place the seeds in the middle, sprinkle in some crushed limestone so that there is a thin layer (about 1/8") and fold the towel again so that the seeds are surrounded by the moist paper towel. Leave about a 1/2 - 1" or so between the seeds. Since there is only about an 16% germination rate for these type of seeds (from tapped trees), I would put in about 8-10 per bag. The odds are at least one will germinate per bag.

6. Put the towel and the seeds in the ziplok bag. Orient the towel so that you can open it on easily though the sealed edge of the bag. Seal to almost closing and blow air in it to inflate the bag and then finish the seal.

7. Place the bag on the germination pad and set it at the correct temperature. (you can use a thermometer and pretest the temperature settings to make sure that you are at the optimum level before you start the whole process) You may want to put a light covering over the bag to help maintain the temperature.

8. Incubate for the recommended time (it takes about 3 weeks) and then check the seeds for signs of germination. Every 4-5 days, evacuate the air in the bag, re-inflate it and reseal.

9. Once the seeds have demonstrated root and shoot initiation, you can transfer them to 1/2 filled pots that have sand on the bottom and 1/2" of crushed limestone/gravel (fine gravel) on the top. Place the germinating seeds on this layer and then cover with another 1/2" of crushed limestone/gravel.

10. Water with a spray bottle and do not let puddle. Water by the spray bottle each day in the morning. When the seedling gets to be 8" tall, then you can reduce the watering to allow the roots to grow downward into the potting soil as they seek moisture.

Some instructions you will find will tell you to put the seeds directly into the limestone/sand mix, but I think it best to do it this way so that you can assure that you have seeds germination under optimum conditions and then you can transplant only those that are truly germination to the pots.

In nature, these plants grow out of rocky limestone crevices and in gravely limestone, so be sure that the transplant receives similar conditions. It also likes to dry out well between waterings. Constantly wet roots will kill the plant.

BTW: Seedlings will not survive frost, but larger trees can.

Let me know how things go!