This month continues the activity of bonsai culture with re‑potting, first potting, root pruning (if necessary), trimming and pinching new growth as well as wiring for shape and design as desired by the owner.

Keep a close check on any trees which may have had been wired over winter.  Tissue will begin to swell rapidly and wire must be removed before the bark is damaged.

As the temperature warms up insect activity will start up.  Check on pest activity frequently and use the appropriate insecticide before damage occurs.

If you haven't prepared your outdoor bonsai area, do so before April 20 (last freeze date).  Clean and remove mildew from your benches or shelves by scrubbing them with a solution of 1 part household bleach to 9 parts of water.  Rinse with clean water and allow to dry thoroughly.  If necessary, treat your benches or shelves with a wood preservative.  Read wood preservative label thoroughly before using it on your display benches.

Check wiring left on trees over the winter and remove if too tight and or if the wire has done its job successfully.

Do not place plants on benches or on any other raised areas above ground until after April 20th.  In this climate zone freezing temperatures are still possible at night.  Historically the last freeze date in the Atlanta area is April 25 (1910); so don't be in a hurry to place your bonsai in display areas!

TRANSPLANT/ROOT PRUNE:

Almond ‑ after flowering, Apple ‑ as buds begin to appear, Apricot ‑ after flowering, Azalea, Bald Cypress when new buds begin to show leaf color, Beech, Birch, Boxwood, Camellia, Cedar, Cherry ‑ after flowering, Chamaecyparis ‑ Hinoki, Cotoneaster, Citrus, Crabapple ‑ as buds begin to appear, Crape Myrtle, Cryptomeria, Cypress, Elaeagnus ‑ as buds come out, Fig (ficus), Fir, Gardenia, Hemlock, Hornbeam, Juniper, Mountain Laurel ‑ after flowers wither and leaf buds appear, Nandina, Oak, Persimmon, Pine ‑black/red/cork bark, Plum ‑ after flowering, Podacarpus, Pomegranate, Privet, Pyracantha, Redbud ‑ as flower buds open, Rhododendron, Sasanqua, Spruce, Sweetgum ‑ as new buds appear, Tamarix, Weeping Willow, Yew, Zelkova.

BRANCH PRUNE:

Apple, Apricot ‑ after flowering, Azalea ‑ after flowering.  Bald Cypress - prune branches ONLY when in active growth; new leaves out to the tip or when dormant if the branch is at least ½" diameter [pinkie size]; if in doubt - don't prune.  Boxwood, Camellia, Citrus, Cotoneaster, Crabapple ‑ after flowering, Fig (ficus), Fir, Gardenia, Honey Locust ‑ after blossoms appear, Hemlock, Nandina ‑ old canes that are too long, Oak, Peach, Pear, Privet, Rhododendron, Serviceberry ‑ after flowering, Tamarix.

TRIM/PINCH NEW GROWTH:

Azalea ‑ pinch/trim new soft growth until end of June.  Bald Cypress - only when in active growth (see above)  Beech ‑ pinch new shoots while still soft leaving 1 ‑ 2 nodes, Birch, Boxwood, Camellia ‑ pinch tips after leaves have hardened, Cedar, Chamaecyparis ‑ Hinoki, Citrus, Cotoneaster ‑ pinch/trim new soft growth leaving 2 pairs of leaves, Crabapple ‑ pinch/trim new shoots, Crape Myrtle, Cryptomeria, Cypress, Elm, Ginkgo, Hackberry ‑ trim after new shoots have 3‑5 nodes during growing season ‑ leave 1 ‑ 2 nodes, Hawthorn ‑ pinch/trim new shoots, Holly ‑ all, Honey Locust ‑ trim elongated shoots leaving 1 or 2 nodes, Hornbeam ‑ elongated shoots to desired shape until summer, Juniper, Maples‑all, Mountain Laurel ‑ trim after shoots have hardened leaving 2‑3 leaves, Oak, Pines ‑Cork bark/Red, Podacarpus, Pomegranate ‑ trim new long soft growth, Pyracantha ‑ pinch/trim new shoots leave 2 pairs of leaves, Chinese Quince, Sasanqua ‑ pinch tips after leaves have hardened, Serviceberry ‑ after leaves harden pinch off tips of shoots, Spruce, Sweetgum, Willow, Wisteria ‑ trim with scissors after blossom withers but before new buds harden, Yew, Zelkova.

FERTILIZE:

If you fertilize before the 20th of this month use a weak water soluble solution or a very low or 0 nitrogen fertilizer to avoid early top growth which could be damaged by late frosts which are common in zones 7/8 prior to April 20.

Apple, Azalea, Bald Cypress, Beech, Birch, Camellia, Cedar, Cherry, Citrus, Cotoneaster, Crabapple, Cryptomeria, Chamaecyparis ‑ Hinoki, Cypress, Elm, Fir, Gardenia, Ginkgo, Hawthorn, Hemlock, Hornbeam, Juniper, Maples, Nandina, Oak, Peach, Pear, Persimmon, Pines ‑ all, Podacarpus, Pomegranate, Privet, Pyracantha, Quince, Rhododendron, Sasanqua, Spruce, Sweetgum, Willow, Yew, Zelkova.

WIRE:

Bald Cypress, Cedar, Cotoneaster, Crabapple, Elaeagnus, Hackberry ‑ after shoots harden, Pomegranate, Privet, Pyracantha, Quince ‑ Japanese. Weeping Willow ‑ only heavy branches before buds come out, Wisteria ‑ wire to shape as new buds appear, Witch Hazel ‑ before buds open.