Girdling, Ringing, Binding

Delaying Bloom by Binding

Sir Francis Bacon: Delaying Roses (1635)
The Seventh is, the Girding of the Body of the Tree about with some Pack-threed; For that also, in a degree, restraineth the Sap, and maketh it come up, more late, and more Slowly.

Ringing and Root Pruning

Daniel: Ringing Herbaceous Plants (1900)

Hedrick: Ringing Herbaceous Plants (1905)

Fagan: Ringing Filler Trees in Apple Orchards (1925)

The Pennsylvania State College—Agricultural Experiment Station, Bulletin 230, p. 35 (July 1928)
Effect of Ringing Fruit Trees on Tree Growth and Reproduction.
Preliminary work was done on the effect of ringing on the viability of the pollen of varieties that are notoriously poor quality pollen producers. Ringing done a week before blossoming had no effect whatsoever on either the amount or viability of the pollen produced from Winesap and Rhode Island Greening apple trees. (F. N. Fagan and R. H. Sudds.)

Michurin: Layering Tube (1929)
The tube prepared in this way is slipped on to the part of the cutting that has been bared of bark B. It closely grips the bark of the cutting on the lines above and below the bared ring. Both halves of the remaining parts of the incised rings are inserted in one of the ends of a glass tube D bent at right angles and having an internal diameter of 12 mm. If a bent glass tube is not available a straight piece F 10 cm. long, of the same diameter (see Fig. 45) may be used.

Bulletin 279 (Aug 1932) pp. 15-16
Pennsylvania Agricultural Experiment Station 45th Annual Report
Ringing Fruit Trees
The filler apple trees in a 20-acre apple orchard have been ringed for eight years; the trees are now 16 years old. The work was begun when the trees were seven years old. The Stayman and McIntosh varieties, which were ringed in early June of their seventh year, yielded four bushels of apples per tree in the eighth year. The untreated trees yield less than one bushel. The filler trees will be removed this year. After eight years of experience in ringing 540 filler apple trees, the Experiment Station feels justified in recommending to the commercial grower the practice of annual ringing of the fillers when they are large enough to produce 3 to 3 bushels of apples. The ringing should be done about May 20 to June 5, when terminal growth is very active and before the terminal bud has formed. (F. N. Fagan)

Fagan: Ringing and Heading Apple Trees (1933)
Discussing the principles and practices of ringing fruit trees to induce earlier fruiting, the author presents the results of ringing and heading experiments in a mixed variety orchard planted in 1917 so closely that the trees were crowding badly in their tenth year. In 1924 all of the filler trees were ringed with the following results, namely increases in 1925 of 3, 3, 1.2, and 1.04 bu. per tree for the ringed Stayman Winesap, McIntosh, Rome Beauty, and Baldwin trees, respectively. A few nonvigorous Baldwin and Rome Beauty trees were killed by the ringing process, suggesting the inadvisability of ringing filler trees that are making weak growth. Despite the fact that severe heading in 1926, 1927, and 1929 of the ringed filler trees reduced their potential bearing surface very decidedly, this group yielded reasonably well and at the same time exerted no harmful effects on the permanent trees.
    As to the technic of ringing, the simple drawing of a sharp knife through the bark was as effective as the removal of a ring of bark and decreased the hazard to the tree.

Pennsylvania Agricultural Experiment Station
Fiftieth Annual Report, Bulletin 352 (Oct 1937) p. 47
Ringing apple trees.—The ringed McIntosh and Delicious trees show the dwarfing effect that results from heavy early bearing caused by ringing, but no trees have died from ringing. Ringed Northern Spy trees set a heavy crop in 1936 in spite of an outbreak of blossom fire blight. The use of grafting tape over the ring seemed to keep blight from entering the cut. Tree Seal paint was not so satisfactory as tape. Ringing continues to be a satisfactory means of securing the largest returns from filler apple trees.—F. N. Fagan

Proceedings of the International Symposium: Plant Growth Substances Calcutta. 271-280 (1967)
Analysis of the effect of ringing and auxin treatment on rooting of mango (Mangifera indica L.) seedling cuttings.
RN Basu, N Roychoudhury, PK Sen
    The mung bean rooting test particularly with the hydrolysed fraction (bound cofactors) seems to be much more related to the actual rooting performances of the cuttings. In chromatograms of ringed cuttings number of active regions indicating root promoting substances were more as compared to those of non-ringed cuttings, and particularly under RIBA the root promoting zones were more extensive.
    That ringing causes synthesis of extractable rooting factors is also indirectly supported by the data presented in Tables 1-3 and also in Table 7.
    Preplanting soaking of ringed cuttings in water, sucrose or 100 ppm solutions of IBA and NAA adversely affected rooting possibly because some of the rooting factors leaching out during that period.
     It is concluded that ringing, in addition to creation of a favourable nutritive condition within the tissues, causes certain changes in protein metabolism and is responsible for the synthesis of a number of rooting cofactors. It is likely that some of these cofactors are more synergistic to chemicals like IBA. Also synthesis of rooting cofactors is possibly enhanced when cuttings are treated with root promoting chemicals.

Basu, R.N., Roychoudhury, N., Bose, T.K. and Sen, P.K., 1968, Vitamins as cofactors of auxins in root formation in cuttings, Proc. Int. Symp. Plant Growth Substances, Calcutta (Ed. S.M.Sircar), pp. 149-155.

Indian Agriculturist 15: 69-85 (1971)
Hormonal Basis of Regeneration of Roots on Cuttings
R. N. Basu
    Amino acid metabolism during regeneration of roots has been studied in ringed (girdled) and ringed plus IBA treated cuttings from fifty days old mango (Mangifera indica L) seedlings employing the protein synthesis inhibitor, chloramphenicol.
    Cuttings without ringing rooted very sparingly, ringing conspicuously increased root formation. Application of chloramphenicol almost completely counteracted the beneficial effect of ringing.
    Changes in amino acid contents during regeneration of roots have been found to be significantly different in the materials which rooted and those which failed to root. Under ringing and ringing plus IBA, where there was profuse rooting, free amino acids and amides like arginine and histidine, glutamic acid, serine and glycine, methionine and valine, asparagine, glutamine and lysine have shown marked decline during the progressive stages of regeneration. Significant incorporation of basic amino acids like arginine and histidine, lysine and few other amino acids into the newly synthesized proteins have been observed in the ringed shoots. In non-ringed cuttings and also in chloramphenicol treated ringed cuttings, where root formation was very insignificant, little change in the contents of the different amino acids was noted.

Bot. Bull. Acad. Sin. 38: 91-95 (1997)
Metabolic changes during rooting in pre-girdled stem cuttings and air-layers of Heritiera
P. Das1, U.C. Basak, and A.B. Das
Mangrove Research Centre, Regional Plant Resource Centre, Bhubaneswar 751 015, Orissa, India
The mangroves of the Mahanadi Delta are unique and include 62 of the 64 mangrove species distributed in India. Vegetative propagation through rooting in stem cuttings and air-layers of Heritiera fomes and H. littoralis, commonly known as Sundri, using IAA, IBA, and NAA is reported. Significant increase in the root number was recorded in the air-layers and the pre-girdled stem cuttings of H. fomes treated together with IBA (5,000 ppm) and NAA (2,500 ppm) as compared to H. littoralis. The maximum number of roots was obtained in H. littoralis with IBA (5,000 ppm) and NAA (1,000 ppm). The overall rooting response was better in the treatments with IBA and NAA rather than with IAA and NAA combinations. Variation in the rooting response due to the exogenous application of auxins was also reflected in the metabolic changes during the initiation, emergence, and development of roots in the cuttings and the air-layers. An increase in the level of reducing sugars was noted in the pre-girdled tissues at initiation as well as at subsequent stages of root development, which was further enhanced by the use of auxins. A decrease in the total sugar, carbohydrate, and polyphenols and an increase in the total nitrogen and a high C/N ratio were noted at the root initiation stage in both species. There was less accumulation of photosynthates and nitrogen in the above-girdled tissues in air-layers than the pre-girdled cuttings. Interaction of IBA and NAA promoted starch hydrolysis during root development and subsequently reduced the C/N ratio and increased the protein-nitrogen activity during the development of root primordia. The auxin influenced mobilization of nitrogen to the rooting zone promoted the rooting efficiency in Heritiera.

Brazilian Journal of Botany 38: 717–728 (2015)
Impact of phloem girdling on water status in desert plants Alhagi sparsifolia Shap. (Fabaceae) and Karelinia Caspica (Pall.) Less. (Asteraceae)
Gang-liang Tang, Xiang-yi Li, Li-sha Lin, Zi-chun Guo, Chang-jun Li, Hui Guo & Fan-jiang Zeng
The removal of a ring of phloem, named girdling, is used for manipulating carbohydrate content above and below the girdle. To investigate the impact of girdling on leaf water status, an experiment was carried out in Alhagi sparsifolia Shap. and Karelinia caspica (Pall.) Less., which grew in the Cele oasis-desert transitional zone with the treatment of control, semi-girdling (SG), and full-girdling (FG). The results showed that after 30 days of girdling, stomatal conductance (Gs), transpiration rate (Tr), root carbohydrate content, root respiration rate, leaf water content and leaf water potential decreased, and leaf carbohydrate content increased under the treatment of FG in two species. On the 1st day, almost all of the treatments showed no change in these parameters, except the full-girdled leaves in A. sparsifolia, which exhibited a reduction in Gs and Tr, and an increase in midday water potential. The treatment of SG showed a similar change to FG on the 30th day in A. sparsifolia; however, in K. caspica, there was no change on the 30th day of treatment. The result of the present work indicated that girdling decreases water status over a long time. Within a short time, however, girdling decreases the Gs and Tr, which lead to an increase in leaf water status in A. sparsifolia Shap. SG also decreased leaf water status over a long time in A. sparsifolia, but not in K. caspica. Most treatments of girdling decreased leaf water status over a long time, but not within a short time. Overall, girdling affects leaf water status, but it depends on time, species, and degree of girdling.

Res J. Chem. Environ. Sci. 6(1): 61-66 (Feb 2018)
Efficacy of Different Root Promoting factors and Stem Girdling on Rooting success of Litchi cuttings
Arghya Mani, Nilesh Bhowmick, Sayan Sau, Sandeep Singh, Vikash Kumar Yadav
A study was conducted on litchi semi-hardwood cutting to find the effects of different root promoting factors like IBA and sucrose and their interaction with stem girdling. The cuttings were prepared and were subjected to varied doses of IBA and sucrose. Various rooting attributes like rooting success percent (%), days taken for sprouting, number of sprout, number of leaves, developing shoot length (cm), root length (cm) and root diameter (cm) were evaluated. Maximum rooting percentage was observed in the treatment consisting IBA @5000ppm (58.33%). IBA @1000 ppm (23.33%) has the maximum effect to induce earliest sprouting. Number of sprouts per cutting is maximum in case of T8 (Sucrose @10%) which was 2.93. T8-Sucrose @10% showed maximum number of leaves per cuttings (5.12). The interaction effect between 10% sucrose girdling showed maximum shoot length of 2.34. T8-Sucrose @10% have the highest root length (5.23 cm). Interaction effect between Girdling sucrose @10% was maximum (5.57) followed by Girdling IBA @3000ppm (5.09) and Girdling IBA @5000ppm (5.09). Maximum root diameter of 1.01 cm in case of T6-IBA @5000ppm and T8-Sucrose @10%. However root diameter was not influenced by any of the factors like growth regulators or girdling. It can be concluded that the cutting treated with a mixture of sucrose and IBA coupled with girdling can be very much effective in providing a higher rooting success in litchi semi-hardwood cuttings.

Ringing and Fruitfulness

Lawrence: Plashing the Pear (1714)
I sometimes plash* the most vigorous Branches, cutting them, near the place from whence they Shoot, more than half through, which effectually checks its Vigor, and consequently renders it more disposed to make weaker Shoots and form bearing Buds. This method of Plashing is also of singular use, when you Would avoid Barrenness, and have only an aukward Branch to make use of to fill the Vacancy, For by this means you may reduce it to what Order you please, so as to answer your purpose and reward you with Fruit. [*to bend and intertwine (branches, stems, etc.) so as to form a hedge.]

Knight: Raising new early potatoes (1807/1820)
A good new variety of an early Potatoe is therefore considered a valuable acquisition by the person who has the good fortune to have raised it; and as an early variety, according to any mode of culture at present practised, can only be obtained by accident from seeds of late kinds, one is not very frequently produced: but by the method I have to communicate, seeds are readily obtained from the earliest and best varieties:
... Having fixed strong stakes in the ground, I raised the mould in a heap round their bases, and in contact with them: on their south sides I planted the Potatoes from which I wished to obtain seeds. When the young plants were about four inches high, they were secured to the stakes with shreds and nails, and the mould was then washed away, by a strong current of water, from the bases of their stems, so that the fibrous roots only, of the plants, entered into the soil. The fibrous roots of the Potatoe are perfectly distinct organs from the runners, which give existence, and subsequently convey nutriment, to the tuberous roots; and as the runners spring from the stems only of the plants, which are, in the mode of culture I have described, placed wholly out of the soil, the formation of tuberous roots is easily prevented; and whenever this is done, numerous blossoms will soon appear, and almost every blossom will afford fruit and seeds.

Williams: An Account of a Method of hastening the Maturation of Grapes (1808/1820)
I took annular excisions of bark from the trunks of several of my Vines, and that the exposed alburnum might be again covered with new bark by the end of autumn, the removed circles were made rather less than a quarter of an inch in width. Two Vines of the White Frontiniac, in similar states of growth, being trained near to each other on a south wall, were selected for trial; one of these was experimented on (if I may use the term), the other was left in its natural state, to form a standard of comparison. When the circle of bark had been removed about a fortnight, the berries on the experimented tree, began evidently to swell faster than those on the other, and by the beginning of September showed indications of approaching ripeness, while the fruit of the unexperimented tree continued green and small.

Noehden: Improving the Productiveness of Fruit Trees (1817/1822)

Noehden: Ringing Fruit Trees (1822)
The theory of this mode of pruning consists in suppressing the direct channel of the sap, and substituting for it from three to seven oblique branches, which, at certain distances, one above another, form a sort of forked passage that will only permit the sap to rise and descend slowly, obliging it to stop and form a great number of fruit buds. The experience of more than a century proves the goodness of this theory, when it is put in practice by skilful gardeners.

Noehden: Training Fruit Trees (espalier) (1822)
The essential point is to lay the branches in a horizontal position. For by training them in this way, the current of the sap is forced to assume a direction, in which it cannot move with the same quickness as it would in its natural channel, which is from the root straight upwards: and the diversion favours the process of forming fruit, by inducing, as has elsewhere been intimated, a slower motion of the sap, and thus affording time for the secretion and deposition of its particles.

Knight Experiments (1823)
It was before well known to gardeners, that any thing which checked the growth of a fruit tree, hastened the production of fruit.
     On two orange-trees from St. Michael's, which had never borne fruit, though we had had them many years, we practised decortication, taking off a ring of the bark of half an inch in width. In the following spring, this year, the gardener expressed to me his surprize, that those limbs were literally loaded with blossoms. He had not been in the secret. We pointed out to him the decortication or ringing, or as we say, the "girdling," and it was found, that while every other part of the tree was without blossoms, those which were operated upon were far too greatly covered with them. In this case we committed a mistake. The orange-tree puts forth only once in a year ordinarily in our climate, or under favourable circumstances, twice. Ringing or girdling should only be executed when the sap is in the greatest possible degree of action. These limbs are not healthy, and we fear will not hold their fruit, but the experiment shewed the principle in its clearest light. The general rule is, to girdle when the tree is in its most rapid state of growth, to make the decortication or ring larger or smaller according to the vigour of the plant, but so little in all cases as to enable the tree to close the wound during the same season. We made a similar experiment on a flowering plant, the beautiful Passiflora Alata, and we threw it by this process into flower, at a season in which it never flowers in the ordinary course of nature, that is, in the month of August. Its usual time of flowering with us, is October and April.

Thacher: Girdling Fruit Trees (1825)
By this simple operation, the following advantages will be obtained:

  1. Every young tree, of which you do not know the sort, is compelled to show its fruit, and decide sooner whether it may remain in its present state, or requires to be grafted.
  2. You may thereby, with certainty, get fruit of a good sort, and reject the more ordinary. The branches so operated upon, are hung full of fruit, while others, that are not ringed, often have none or very little on them.

The Gardener's Magazine 4(16): 484 (Oct 1828)
RINGING Trees.— I have found a very great economy in ringing, by the use of the common scorer used by woodmen in marking timber trees. (fig. 123.) I ring many of our shrubs and ornamental trees, to throw them early into blossom, and to cause them to produce larger blossoms. I have flowered the tulip tree at seven years from the seed-bed, and I have a very fine set of dwarf fruit trees all circumcised below the surface.—John Brown. Near St. Albans, March 21, 1828.

Laffay: Camellia Seeds (1830)
... having seen Camellias filled with seeds in a garden, he remarked these plants with more attention, and perceived, that the most of them had their branches mutilated and the ends broken off.

Downing: Ringing Fruit Trees (1837)
RINGING (incision annulaire, of the French,) is a well known operation, occasionally performed upon fruit trees, both with a view of inducing fruitfulness, and of hastening the maturation of fruits. The practice is one of very ancient origin, but was revived among the moderns by Du Hamel, who published the result of his very successful experiments in the Memoire de l'Academie des Sciences, for 1778. Since that period it has been in a considerable degree resorted to in England, to force the production of blossom buds on sterile fruit trees, and to hasten the period of ripening of fruit already formed, as well as to increase its size. When practised for the former purpose, the operation must be performed in the spring; but when it is intended that the effect shall be produced upon the fruit of the current year's growth, the incision should be made when the branch is in flower.

Gunnell: Camellia japonica var Harrisonii (1841)
The only reason I can offer for this unusual quantity of buds, is, that the binding of the plants, in that stage of their growth when they were inarched, checked the flow of the sap, (the variety being a rapid grower,) and consequently induced the formation of flower buds.

Donald Beaton: The Cottage Gardener 11(271): 177 (Dec 8, 1853)
That trees have the power to heal over large wounds made in them, by accident or by design, is a fact that has been known, and that has never been disputed, for ages. Grafting and ringing fruit-trees are familiar processes founded on such knowledge, ...

Russell: To obtain Fruit from Barren Trees (1859)
I wish to describe to you a method of making fruit trees bear that I blundered on to. Some fifteen years ago I had a small apple tree that leaned considerably. I drove a stake by it, tied a string to a limb and fastened it to the stake: The next year that limb blossomed full, and not another blossom appeared on the tree, and as Tim Bunker said, "it got me a thinking," and I came to the conclusion that the string was so tight, that it prevented the sap returning to the roots; consequently, it formed fruit buds. Having a couple of pear trees that were large enough to bear but that had never blossomed, I took a coarse twine, wound it several times around the tree above the lower limbs, and tied it as tight as I could. The next Spring all the top above the cord, blossomed as white as a sheet, and there was not one blossom below where the cord was tied. A neighbor seeing my trees loaded with pears, used this method with the same result. I have since tried the experiment on several trees, always with the same result. I think it a much better way than cutting off the roots. In early Summer, say June or July, wind a strong twine several times round the tree, or a single limb, and tie it, the tighter the better, and you will be pleased with the result: the next Winter or Spring the cord may he taken off.

Beaton: Propagating stem-rooting lilies (1861)
Mr. Knight made an experiment for getting early Potatoes to seed by planting them on a ridge, and when the plants were ready to bloom he washed away the soil of the ridge to prevent them making young tubers, and so force the whole strength of the plants or roots into the stems and foliage to see if that would force them to seed. Another form of that experiment is applicable to all bulbs and tubers which form roots on the flowering-stems, as the Japan Lilies and others do. Pot such bulbs or tubers with the neck of the bulbs just at the surface, and when the stem is an inch or two put an empty pot over it, introducing the stem through the hole at the bottom of the pot, then earth up the stem, and when it roots and fills the upper pot separate from the bulbs, then cross it.

JCH: Ringing Fruit Trees (1869)
This year the appearance of the three branches above the cut stem was one mass of white blossom, there being only one blossom on any other part of the tree; and there are at this time, besides numbers that I have removed, thirty-six Pears, healthy, and apparently going on to maturity.

American Farmer, 5(6):193 (1876)
A correspondent of the American Agriculturist says: "To obtain fruit from barren trees, take coarse, strong twine, and wind it several times about the lower limbs of a tree and tie it as tight as possible. The next spring all the top above the cord will be as white as a sheet, and there will not be one blossom below. A neighbor seeing his trees loaded with pears, used the same method with the same success."

Daniel: Ringing of Herbaceous Plants (1901)

Drinkard: Fruit-bud formation and development (1911)
Prof. Macoun: Proc. Soc. Hort. Sci. (1911)
It has been a little theory of mine, not borne out by any actual experiments, that the formation of fruit-buds is due in part to the retardation of the elaborated sap in the upper part of the tree. For instance, we find that ringing a tree will cause the development of fruit buds. We find also that a branch which is partly broken will fruit perhaps two or three years before the other part of the tree. We find that a tree which is top-grafted will fruit sooner than a tree which is not. It strikes me that there may be some relation between the retardation of the elaborated sap by ringing, breaking or grafting and the formation of fruit-buds. It has also been noted by fruit-growers that a dry season is followed by a good crop of fruit the next year.

Jeffrey: Seeds on horseradish and Lilium candidum (1915)
Physiological sterility is frequently due to entirely different causes than genetical lack of harmony, as for example in the horseradish or the potato (Solanum). In the former it has been found possible to bring about the formation of fertile seed by simply girdling the top of the subterranean storage region of the plant, so as to prevent the undue descent of assimilates. The common white lily, Lilium candidum, presents a similar condition, for here the setting of seed takes place only when the leafy flowering axis is severed from its bulb and kept in water.

Husmann: Ringing Grape Vines (1920)
In the experiments conducted at the Fresno Experiment Vineyard, 12-year-old ringed Panariti grafts on 10 different resistant stocks trained to stakes (vines 8 by 8 feet apart, or 680 to the acre) during 1917 and 1918 gave average annual yields per acre ranging from about 5.8 tons on the poorest stock to 10.35 tons on the best stock, the average on all the stocks being nearly 7 1/2 tons. The check vines with like treatment and care averaged only 2 1/3 tons to the acre. Ringed 5-year-old Panariti grafts on 18 different resistant stocks, with trellis training (vines 8 by 8 feet apart, or 680 to the acre) during 1917 and 1918 averaged annually over 5 tons to the acre, while the check vines averaged only 1.9 tons to the acre.

Coit: Girdling Avocado (1921)

Traub: Artificial Reversal of Growth Dominance in Amaryllids (1935)
In a large number of trials, self or cross pollinated flowers of excised amaryllid scapes, especially those of Hippeastrum, placed in water or nutrient solution, have in the great majority of cases produced seeds. Within limits, the number of seeds per capsule seems to be largely a function of the relative size ("fleshiness") of the peduncle. Species in five Genera have been used in the experiments,— Hippeastrum, Crinum, Haemanthus, Zephyranthes and Narcissus. In Zephyranthes the number of seeds produced has been below expectancy, especially in the case of Z. Atamasco and Z. treatieae, which may be due in part to the relatively small size of the peduncle. Z. robusta, with a larger peduncle, produces a relatively larger number of seeds per capsule. Although abundant seeds have been secured from excised scapes of Crinum asiaticum, C. longifolium album and C. longifolium roseum, only an abundant number of fleshy fruits without seeds were produced in the case of C. augustum, a doubtful species which does not set seeds under Florida conditions. A Burbank hybrid Crinum produced many small seeds in each pod which were not viable. Approximately 5 percent of flowers on excised scapes of Haemanthus multiflorus have produced seeds.

Jacob: Girdling Grape Vines (1931)
Interest in the practice of girdling Thompson Seedless (Sultanina) vines for the production of table grapes has increased greatly in California during the past three seasons, and the time seems not far distant when most of the Thompson Seedless grapes produced for table use will be from girdled vines. The practice of girdling Black Corinth for the production of the "Zante" currant raisins of commerce is an old one, and is in use wherever this variety is grown.

Roberts & Struckmeyer: Vernalization & Photoperiodism (1948)
Poinsettia plants in short days, but too warm at night to initiate blossom, can also be brought into blossom by wrapping taut rubber bands about the stems near the tips. When blossoming is induced in this manner, characteristic changes in the anatomical structure were found to occur above the point of banding.

Tree Planters' Notes No. 28, pp. 6-7 (Apr 1957)
Longleaf Cone Production Doubled by Ringing
W. F. Mann, Jr., and T. E. Russell
Ringing or partial girdling has more than doubled cone and seed production on some second-growth longleaf trees near Alexandria, La. Since this treatment is easy to apply, it may be useful in the management of seed-producing areas or as an aid in securing natural regeneration on areas lacking adequate seed trees.

Woods: Douglas fir Pollen (1989)


Apparent competition between vegetative phase and fruiting phase

Root-bound / Root pruning