By Rachel Seville
DOUBLE-FLUSH PINES SUMMARY SHEET
Double-flush pines – Japanese Black Pine, Japanese Red Pine, Aleppo Pine, Pitch Pine, Yellow Pine, Loblolly Pine.
Typically grow in low elevation, coastal regions in a warm, humid environment with a longer growing season.
Spring is the ideal time to repot but NOT to carry out needle plucking, wiring, bending or pruning as this will damage new growth, candles and buds.
Summer (June) is the ideal time to de-candle double-flush pines. De-candling means cutting off a new candle completely at its base.
How to de-candle – identify weak, medium and strong areas. Do NOT de-candle the weak areas. De-candle the medium areas and pluck old needles back leaving 10-12 pairs of needles per shoot. Wait 12-14 days. De-candle the strong areas and pluck back old needles leaving 5-7 pairs of needles per shoot.
This allows weaker areas to strengthen, it gives medium areas a head-start over the stronger areas and it weakens the stronger areas. This will achieve balance across the entire tree. The de-candling process will produce shorter needles.
Notes – do NOT de-candle the medium areas and then forget to de-candle the stronger areas as this will achieve the opposite effect. Also, if a tree is sick or weak, do NOT perform de-candling at all.
De-candling timings – this will depend on individual environments but as a general rule of thumb, large trees can be de-candled from early to mid-June, medium trees from mid to late-June and shohin trees from late-June to early-July.
Fertilization – for trees in early development, fertilize with a high nitrogen feed from early Spring until late Autumn. This will strengthen the tree, maximise growth and increase bud production for the following season. A seaweed tonic can also be used throughout the season.
Fertilization – for trees in mid-development or refinement, fertilize with a high nitrogen feed from February / March but stop feeding 4 weeks before de-candling. Do not feed immediately after de-candling as this will help keep needles short.
A seaweed tonic can still be used throughout the season. This is not a fertilizer because it does NOT contain nitrogen. It is like a vitamin supplement that will keep the tree in optimal good health.
Fertilization can recommence when the 2nd flush of growth has hardened off typically in August / September. When candles harden off, they tend to get darker in colour and the needles become sharper.
Pines produce three types of buds – terminal buds at the end of candles, needle fascicles at the base of old needles and adventitious buds (back-buds) on older wood.
September / October is the ideal time to needle-pluck which will help induce back-budding. Remove all 2-year-old needles, remove some 1-year-old needles and leave all new needles.
Cut back 2nd flush candles to an average size across the entire tree. This will help produce more terminal buds. Candles can be pinched or cut with scissors.
Where there are three or more candles at the same point on a branch, cut back to two. Ideally choose two laterally-orientated candles. Overly long needles can also be trimmed down at the same time.
Autumn is the ideal time for wiring, heavy pruning, heavy bending, creating jins and creating sharis.
Japanese Black Pines and Japanese Red Pines do NOT like cold temperatures (-6.5º) so protect in an unheated greenhouse, garage or cold frame.
NEVER withhold water from your pines if they require it. The techniques described above will achieve a shorter needle length and a balanced growth pattern across the whole tree better than restricting water which can ultimately kill the tree.
SINGLE-FLUSH PINES SUMMARY SHEET
Single-flush pines – all pines not on the double-flush list including Japanese White Pine, Scots Pine and Mugo Pine
Typically grow in high elevation, mountainous regions in a cooler environment with a shorter growing season – no time to produce a 2nd flush of growth.
Spring is the ideal time to repot but NOT to carry out needle plucking, wiring, bending or pruning as this will damage new growth, candles and buds.
Single-flush pines must NOT be de-candled as they will NOT produce a 2nd flush of growth in a single season.
Candle pinching is when the candle is shortened either by pinching it with fingers or by cutting it with scissors.
How to candle-pinch – identify weak, medium and strong candles. Do NOT pinch the weak candles. Pinch the medium and strong candles back to the average length of the weak candles. This can all be done at the same time. This will promote balance and promote an even growing pattern across the entire tree.
Timing of candle-pinching – this can be done from late-Spring to mid-Summer. It is best done when new needles start to emerge from the candles. Always pinch somewhere above the first set of needles otherwise the candle may die.
Do NOT candle-pinch too early in the season otherwise the needles will become too long. The tree will put energy into needle growth rather than candle extension.
If more than two candles exist at any one point, always cut back to two to avoid ugly swelling. Choose laterally orientated candles if possible. Do not pinch any candles on a branch if it is particularly weak.
The Jiku – some pines produce flowers followed by candles. A jiku is formed where the flowers were which elongates the internode. If other shorter shoots are present, the jiku can be cut off completely. If not, they can be left as they may back-bud.
Fertilization – for trees in early development, fertilize with a high nitrogen feed from early Spring until late Autumn. This will strengthen the tree, maximise growth and increase bud production for the following season. A seaweed tonic can also be used throughout the season.
Fertilization – for trees in mid-development or refinement, do NOT feed in Spring otherwise the new needles will become too long. Wait until the new candles have hardened off (June to early July) and then start fertilizing. When candles have hardened off, they become darker in colour. In the case of Japanese White Pines, it happens when the candles drop their sheaths.
Continue feeding until late Autumn as this will help new bud development for the following season. A seaweed tonic can be used throughout the growing season.
September is the ideal time to needle-pluck single-flush pines. Remove almost all the needles from the previous year but leave all the needles from the current year. This will help to induce back-budding.
Autumn is the ideal time for wiring, heavy pruning, heavy bending, creating jins and creating sharis.
NEVER withhold water from your pines if they require it. The techniques described above will achieve a shorter needle length and a balanced growth pattern across the whole tree better than restricting water which can ultimately kill the tree.
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