Five ficuses trunk fusion

I grown several specimen of Ficus Religiosa intending to fuse them together from the beginning, and first attempt in trunk fusion is going well so far (I'll update on it later). Now it's time for another one. My plan is to get something resembling these:

The idea is to fuse several trees, let one of them grow straight to make an apex and bend others at different heights to form branches. I measured available plants and made a wire model of today's procedure:

Here are 5 participants, 5 month old Ficus Religiosas, grown from seeds. They were initially sowed in small nursery cell container in December 2016, then in January 2017 I slip potted them to slightly larger containers, and finally in April 2017 slip potted again to a half cut 500ml glasses.

Now it's time for a proper repotting and root maintenance. Slip potting traces were very visible in roots, as kind of layers of root ball density. I pruned the roots removing ones growing downwards and keeping radial structure. Some root balls were relatively modest and easy to clean up:

And some were very messy and large. Especially this one, I spent a lot of time untangling roots and cutting non-radial ones. This plant is 10mm thick just above ground and had even thicker curled roots below. That's what I got after pruning:

Done with roots, I started binding. This time I decided to use rubber bands cut from bike tube instead of steel wire. It's easy to make very tight knots with it and it's supposed to stretch as trunk grows, hopefully not damaging the tree at all. First I bound two trees:

Then added third, the thick one. They actually already look somewhat fused:

I used curly roots of the fatso as additional bonding. Hope that's OK in terms of nebari.

Then I added last two trunks and started to tighten them higher up:

Binding complete:

Another task needed to be accomplished today is wiring. I needed "branches" to grow sideways immediately, because now they are still small and easy to bend and also this way they're going to get more light. That wasn't hard, I used some rubber- and plastic wrapped aluminum wire:

Despite I kept roots moist all the time, the top leaves began to wither by the end of third hour of work. Luckily, it was almost done and after pruning some too large or overlapping leaves I planted the result into a pot. I used a mixture of 50% akadama, 25% compost, 15% pumice and 10% lava rock. Watered generously with root hormone and put to greenhouse.

 Next day it's looking good, withered leaves are stiff again, no visible signs of damage.

New greenhouse

Finally I've got a larger greenhouse so I can put every plant in a larger separate pot. The small nursery really was limiting their growth by now, so repotting was imperative. During repotting I was able to see some relatively large aerial roots:

There was a couple seedlings which have grown symmetrically sharing one cell:

I decided to practice in pruning on them. Anyway, they have tangled their roots so much that it was impossible to separate them without some damage. 

So went on and cut their roots to maintain kind of radial structure, but keeping some of roots at the same time:

Next day after root pruning, the first one (with fewer roots left) have withered a little. I believe that's because smaller root system can't maintain the same amount of leaves. So I've pruned their tops as well. After cutting stem ooze a little of nice white sap:

I've slip potted all the rest of the plants without much invasion, except for a couple of smaller ones, which have fallen behind their little brothers, like the one here. These I've just pulled out like carrots and put them into freed nursery cells. I should get rid of them completely if they don't catch up with others.

This is how greenhouse looks like now:

Larger volume requires more power to heat and more effort to keep humidity high, but after some experiments I've managed to achieve 98% RH and 24°C.