Queensland bottle trees are a unique tree, native to Australia. As the tree matures, the trunk grows naturally into a shape that strongly resembles the classic shape of a wine bottle. The reason for the shape is for the tree to store water. This makes it an excellent plant for regions where ordinary trees have a hard time making it through the dry season.
There are several ways to propagate a Queensland bottle tree. These include from seed, from cuttings, and by transplanting. It can be grown out-of-doors in appropriate climates, grown in pots, and even made into bonsai.
This is the most common and the easiest way to grow a bottle tree. The seed pods form on a mature tree in late summer. The best way to harvest a seed pod is to use a pair of garden clippers and snip off a pod that has burst just enough to begin exposing the seeds.
While wearing gloves, use a pair of pliers to crack the seed pod and remove the seeds. The seeds have tiny hairs on them that can be irritating if they embed in your skin.
Mix equal parts perlite and peat moss to create a suitable seed bed in a well-drained 4-inch plastic pot. Moisten the soil by misting, then allow it to drain for at least 20 minutes before adding the seed.
Add one seed to the pot, sprinkle soil over it, but do not completely cover the seed. Create a terrarium effect by perforating a piece of plastic and stretching it over the pot.
Place the pot in a warm, sunny location, where the pot will be kept at about 80 degrees Fahrenheit. If your growing area is a little chilly, use bottom heater for the pot to maintain the desired temperature. Add a little water to the pot after seven days, but do not soak. After about fifteen days, you might begin to see growth. However, from comments by various growers, the germination can even take months. Be patient.
Once the baby trees are about three inches tall, you can transfer them to a larger pot.
If you plan to grow the tree out-of-doors, transplant it outside after temperatures have consistently reached seventy degrees Fahrenheit. Make sure that it is in a well-drained location where it can get plenty of sunlight.
The trees can become quite large, so be sure to allow ample room for the trunk and spreading branches to grow.
Growing bottle trees from cuttings is a little more challenging than growing them from seeds, but it can be done. Take the cuttings from small branches on a mature tree during the dry season. This helps prevent excess loss of nutrients and moisture from the parent tree.
Bottle trees are exceptionally vulnerable to damage from bruising or cutting, so be sure to seal the cut with a pruning cement to help the tree heal.
Trim the end of the cutting at a 45-degree angle and remove most of the leaves and extra branches. Prepare a perlite and peat potting soil similar to the starting mix used for seeds. Again, make the soil damp but not soaking wet and be sure that it is well drained before inserting the branch into the potting mix.
Dip the cut branch in a rooting hormone mixture. Make a hole in the potting mix, add the cutting, and tamp the soil in around it to make sure there are no air pockets. Tend the cutting in the same way as the seed, keeping watering to a minimum. Roots should begin to form in 80 to 90 days, according to Google Patent CN 101828511A.
Most growers agree that it is easier to start a bottle tree from seed or from a transplanted seedling.
In Pots or as Bonsai:
Although bottletrees can be grown out of doors in areas where temperatures are warm most of the year, they can also be grown in pots. This is because the tree will grow to suit the size of the root ball. The bottle part of the little tree will form underground first, and then expand to grow above the pot. The size of pot will, to some extent, influence the size of the tree.
As with most trees that would normally grow to full size, bottle trees can be made into interesting bonsai through root trimming and judicious applications of water or fertilizer.
Bottle trees handle transplanting very well, even as fully-grown mature trees. The key is to include as much of the root ball as possible, to package it well, and to support the tree during movement. They tolerate heavy pruning of the tap root and of the canopy, which makes it easier to move the tree. They can handle being out of the ground for as long as three months, with proper care.
Overall, the bottle tree is hardy, tolerating extremes of temperature and quite a bit of neglect. The main thing to is to be very careful not to overwater it, and to keep seedlings, cuttings and young trees warm.