This looks worse than typical transplant shock, which generally just involves some lower leaf yellowing and shedding without being accompanied by major wilting. Were the trees monitored closely for watering needs (plus watered-in well just after planting) since they was installed? Were the root balls loosened-up well, with roots disentangled, during the planting process? If not, that can hamper efforts to keep the root ball well-hydrated since the surrounding soil texture is different and will retain, absorb, and drain water differently.

The way you dug the planting hole and positioned the root flare is fine. While amendments like Bio-tone aren't really needed, its use shouldn't be a factor in this case. Compost (Leafgro) can be a good amendment for compacted soils or those low on organic matter, though it too isn't always needed for trees. Even so, your use of it likely had little impact on this situation, though it might be more influential for water retention if it wasn't well-blended with the existing soil when it was added.

The degree of dehydration suggests that the trees will unfortunately not survive, but it's hard to be certain. At the very least, these leaves will shed, some branch dieback might occur, and some root loss might have occurred as well. Cherry roots are intolerant of staying too wet, but this type of leaf death doesn't look like it was caused by over-watering, as the wilting resulting from that tends to cause leaves to turn yellow-green instead of brown.

If something unrelated to planting method caused dieback, the trees might have a borer or infection issue; cherries are vulnerable to several pests and diseases (this page discusses flowering cherries, but applies to them as well as fruiting types), usually when already under stress or after injury. Canker infections or wood-boring insects might have invaded the trunk(s), though once advanced, outwards signs of those issues can involve bark cracking, sap oozing, fine-textured sawdust (either in "toothpick" form sticking out from the bark, or loose falling to the ground at the trunk base), or holes (the diameter of which would depend on the borer). It would be unusual, but not unheard of, to have two trees this young succumb to borers or canker. Prior drought stress or over-watering might have been complicit, though the nursery wouldn't necessarily have known the trees were suffering if they looked fine at the time of sale, since symptoms can lag behind damage.

For now, it might be more prudent to replace the trees (especially if they are under warranty from the nursery). Recovery of the current trees is not certain, and it would probably take several weeks, using-up valuable establishment time.

Our Growing Stone Fruits in a Home Garden page has more information that might be useful, not as much for this situation since the trees might be beyond help, but for general cherry growing tips.

Miri

Good morning,

Hello Ian,

You can also perform a scratch test on any leafless branches to see if they are alive or dead, which looks at the cambium layer (this is the living tissue just underneath the bark which conducts water and sap into the canopy and down to the roots). To be fair, a branch that looks alive and remains flexible might actually be dying and just not have fully-dead or dried-out cambium yet, so it might be a little misleading at first, but over time it will become obvious, and may save time from waiting a full year to see if a leafless plant is still alive.

Honestly, though, a plant that remains leafless for a full growing season would probably not be worth rehabbing since that implies it is quite weak and may also have irreparable root dieback. Keep in mind as well that any new growth arising directly from the root system or below the graft low on the trunk will not be the cultivar of tree you purchased, and will probably not be worth keeping as a result (the fruit will differ, if it fruits at all, and it won't be as dwarf, disease-resistant, or have any other traits that the selected cultivars did).

Other than monitoring it for watering needs, there is nothing else you need to do while you wait for it to recover. Don't fertilize, since a plant without foliage will have low nutrient needs and the soil is not likely to be deficient in anything it needs right now.

We don't have data on how effective olla-type watering would be. Instead, the simplest approach is probably just to use a tree-watering bag (Treegator being one brand name example, but there are others, and we're not recommending one brand over another). It will slowly drip water into the root zone and can be refilled as needed, once the soil around six inches down has become somewhat dry to the touch (at that depth). Installing a drip irrigation system can also conserve water and put it right where it's needed, but may clog over time or suffer from animal chewing (especially when they're thirsty) that requires repairing to fix leaks.

If a tree has become too large to use a watering bag around its trunk (not only due to trunk diameter, but also due to root spread), then a DIY solution can be to drill small holes in the base of a 5-gallon bucket (or several buckets) and place them around the root area filled with water to slowly drip-irrigate the tree, just like a watering bag would. They can be moved around to wherever they're needed, and like the bags, hold a set volume of water so you know how much you're watering a given plant.

Miri