Gadenin日本語Get the appLate winter, while the tree is bare
This is when all the structural work happens. On young trees, remove competing leaders, keep one dominant trunk, and select scaffold limbs at wide angles spaced up the trunk. On mature trees, take out dead, broken, rubbing and low-hanging wood and nothing more. Do it before the buds swell so cuts close quickly.
Winter is also sanitation season. Rake up fallen shucks, leaves and prunings from under the tree and remove them from the garden, because scab spores and overwintering insects sit in that debris waiting for spring rain. This is the single most useful hour of work a home grower can do against scab.
If your trees are crowding one another, this is when to take one out. It feels like vandalism and it is the reason a mature planting keeps bearing on its inner limbs.
Spring: bud break, bloom and zinc
Pecans leaf out late, well after most other trees, which usually keeps them clear of the worst frosts. When new growth does appear, watch it: small, narrow, crinkled leaves with unusually short spacing along the shoot are zinc deficiency, and the correction is a foliar zinc spray on the expanding leaves, repeated on the new flush. Soil zinc is largely wasted on alkaline ground.
Bloom follows on the new growth. Catkins hang from last year's wood and the small female flowers sit at the tips of the current season's shoots. The whole business is wind-driven, so nothing you do for insects matters, and weather during the shedding window decides a great deal. Walk the trees during bloom and note which sex is active first on each tree, because that is what tells you the timing group.
Apply nitrogen as growth starts if the tree is bearing age, and keep a weed-free mulched circle. Grass under a pecan competes for water at exactly the wrong time of year.
| Phase | What the tree is doing | Your job |
|---|---|---|
| Late winter | Fully dormant | Prune structure, rake debris, thin crowded trees |
| Bud break | Late leaf-out | Watch for zinc deficiency; feed bearing trees |
| Bloom | Catkins shed, female flowers open | Record which comes first on each tree |
| Early summer | Natural nut drop | Thin clusters in a heavy year; cut out webbed clusters |
| Midsummer | Nut sizing | Deep watering; watch for scab and aphids |
| Late summer | Kernel filling | Water without fail; do not let the tree dry out |
| Autumn | Shuck split and drop | Gather every two or three days; cure the nuts |
| Early winter | Leaf fall, dormancy | Clear shucks and leaves; weigh and record the crop |
Summer: the part that makes or breaks the kernel
Early summer brings the natural drop, when the tree sheds unpollinated flowers and then surplus nutlets. Let it happen. In a year when the remaining set is clearly enormous, thin clusters on the limbs you can reach by about a third once the drop has finished; this is the only real defense against the barren year that follows a huge crop.
Midsummer through late summer is when the kernel fills, and it is the most water-hungry phase of the pecan year by a wide margin. A mature tree needs deep soaking in any dry spell right through this period. A tree that runs short of water while filling gives shriveled kernels no matter how good the set was, and that failure is invisible until you crack the nuts in autumn.
This is also when scab does its damage in humid regions and when aphids build up. Watch the shucks for sunken black lesions and the leaf undersides for sticky honeydew, but resist spraying a large tree with broad-spectrum insecticide, which reliably makes aphids worse by removing their predators.
Autumn and the record that pays off next year
Harvest begins when the shucks brown and split along four seams, starting at the top of the tree and working down over three to five weeks. Gather every two or three days, daily in wet weather, because nuts lying on damp ground take up moisture and the oily kernels go moldy and rancid. Cure the crop in a single layer somewhere dry and airy for two to three weeks, then store in the shell.
Once the last of the crop is in, close the year on paper. Write down the weight of nuts harvested, the week shuck split began, whether the summer was wet or dry, when the first scab spots appeared, and the position of each tree with its timing group. None of that is interesting in the year you write it.
It becomes valuable in the third year, when the pattern appears. You will be able to see your trees' alternate-bearing rhythm and know in spring whether this is a year to thin nuts, you will know from the spring weather whether to expect a scab year, and you will know whether a poor crop was a pollination failure, a drought or simply the tree's off season. With a tree that lives a century, the notes outlast every other tool you own.
The four things worth recording every single year are the harvest weight, the week the drop started, the bloom sequence on each tree, and the summer rainfall in rough terms. Four lines a year is enough to explain almost any crop failure you will ever have.