I said they were well drained, but I think they're just potted in a regular potting soil. Should I amend with some sand/vermiculite? I am also going to cut away the brown, I think

i suspect a water issue ... and it looks like sunburn ...

i suspect a lack of water.. a while back ... during the hot season ...

with conifers.. the injury.. can be months.. before the needles fail ... and sometimes.. even the season before...

e.g. i can have winter wind burn .... but the evergreen needles dont brown until the heat of summer impacts the plants ability to pump enough water to the injured leaves ...

i do NOT recommend cutting it off ... notice the growth tips are still alive ... unless you can predict how it will impact the trees growth ... in other words.. if this is the leader i would leave it.. need a pic of the whole ...

you need a special media for trees in and you dont mention pot size ... if you can not make your own al's gritty mix [a GW fave] .... then i suggest a bagged cactus mix ... perhaps cut with a peat mix ...

lets see a pic of the media you are using .... you say its drains well .. i want to know.. how much it retains .... peat is usually the variable ....

finally ... they are not children.. they are not hungry ... this is not a food issue ... but.. because it is potted ... you may need A LITTLE fert once in a while ... but not in fall ... IMHO ...

for sure finally .... i would not have this plant in full sun... in a pot.. on say.. cement patio.. during noon to 6 pm.. the heat of the day .... but i would have it in as bright a spot as i could... its all about.. how hot the pot and roots get ... where is yours kept???

ken

The only time my gold Hinokis burn is when they are in a pot or recently transplanted and in full sun. Larger ones in place for some time with no extra water in our dry summers do not sunburn here in full sun and decent soil.
Mike

I have two of these same plants that were both doing well for 3 years in different locations. This past winter was extreme, and the south face of one of them got sunburnt much more severely than yours, though the other one looked great. These plants always lose old foliage and get brown in the middle, so it's nothing to worry about. It only takes a few minutes to knock off all the old dead stuff - I do this every winter.

I moved the burnt one to another location so that it still gets plenty of sun, but now has a bit more protection...I'll see how it looks after this next winter. If needed, I'll move it again next March or April. AL