Provided by UF/IFAS
Containerized trees may be installed at this time of year. In well-drained, sandy soils, dig a hole slightly shallower than the root ball and twice as wide. Root ball will settle as media decomposes. In compact or poorly drained sites, plant 2-3 inches above grade.
Red line indicates grade. The tree was planted at least three inches too deep.
Deep planting is linked to premature decline. Use backfill to refill hole. If using bagged soil/topsoil/manures/et cetera thoroughly blend at 60/40 ratio. 60% or more native soils with 40% or less bagged manure/peat/compost. Break up clumps and loosen sides of the hole.
More than a “finishing touch,” mulch outside the root ball helps reduce weed competition. Prevent soil compaction with a 2-3 inch organic mulch layer to the drip-line. Mounding mulch around the trunk is known as volcano mulching. This has a similar effect as planting too deeply. Volcano mulching is not recommended.
Volcano mulch has a negative impact on tree health.
Correct root defects for stability and tree health.
Ideally, roots radiate from the trunk, extending out into the landscape. ‘Shaving’ the periphery with a sharp knife, scissors or shovel is appropriate if roots bear the imprint of the container. If they are circling, trim deflected roots where they bend. New, regenerated roots will radiate away from the trunk.
Stem girdling roots restrict nutrients and water to that portion of the tree. Remove stem girdling roots at the point of origin to reduce the likelihood of tree decline.
Water is the best amendment.
Temperature, cloud cover, wind, soil characteristics and season of planting play a role in how much water is needed. Apply water to the root ball and slowly enough that it is able to soak into roots. Research at the University of Florida indicates consistent irrigation is more beneficial than large volumes of water applied inconsistently. Manage root available air and water with proper irrigation and not planting too deeply.
In sandy well-drained soils, apply a gallon of water per inch of the caliper. Daily, for two weeks. Every other day for two months. Weekly until established. Rainfall is an excellent substitution for irrigation. ½ inch of rainfall will percolate to a depth of 6 inches. Do not water-saturated soils.
As measured directly across, this tree is slightly more than one inch.
So what is caliper?
Caliper is a measurement of trunk thickness at twelve inches above the root. A 1.5” caliper tree means that the trunk is 1.5” across. Larger nursery stock requires more water per irrigation event and for a longer duration. Nursery stock at 2-4 inch caliper would need daily irrigation for a month. Every other day for 3 months and weekly until established.
Should I put fertilizer in the hole?
We want to give trees a good start by providing everything they need. However current recommendation is not to place fertilizer in the hole or fertilize at planting. Fertilizer rates, timing, and formula vary by species.
Staking is temporary.
Not all trees require staking. Loosen and re-position straps to prevent girdling stems. Allow the trunk to move slightly. This is an excellent publication by Ed Gilman and Laura Sadowski with tree planting practices and illustrations. Best wishes for good success. Call or comment below with questions. Happy Gardening!
On the fifth day of winter, a dear friend gave to me
Five days of rain.
Four assorted birds.
Three flowering shrubs.
Two pruning friends.
And a cardinal in a crape tree.