How to prune peonies during the dormant period? Dormant-period pruning of peonies
How to prune peonies during the dormant period? Dormant-period pruning of peonies
1 Current status of peony cultivation and use in the Beijing area
Peonies have a cultivation history of more than 1500 years in our country and are a preciousdistinctive flower。The history of peony cultivation in the Beijing area is also very long; since the Liao、and Jin establishedtheir capital here, it gradually flourished and reached its peak in the Ming Dynasty。
Although the famous gardens and former capitals within Beijing no longerexist, peonies are very widely used in garden applications, often for creating plant landscapes,uniquely possessing the capital's character。Since ancient times there has been“a saying, "cultivate flowers for a year, view the flowers for ten days"”In order to better apply peonies in garden plantlandscapes, in addition to breeding excellent new cultivars, one should alsopay attention to cultivation and maintenance techniques, so that peonies create more beautifulscenery during their relatively short flowering period. Among these, because the peony is a perennial small shrub with strong root suckering, the new shoots'question of whether to keep or remove them, and how to prune old shoots, have become cruciallinks in peony cultivation and maintenance。
2 Growth habits of peonies
The peony is a perennial deciduous small shrub, with a plant height of 1～2 m, short branches, and thick yetbrittle stems. Current-year branches are green, old stems are grayish brown, and flowers are borne at the topof current-year branches, solitary, large and beautiful, with red、pink、purple、white、yellow、green and many other flower colors. The flowering period is from the end of Aprilto early May。It has the characteristics of preferring coolness、and avoiding heat、and preferring light; it is slightly shade-tolerant and relatively cold-resistant。It requiresloose、fertile、well-drained neutral loam or sandy loam, and avoids heavy clay soil orplanting in low-lying waterlogged places。
The peony bud is enclosed by 6～8 scales, so the peony bud is also called“a scalybud”。The peony overwinters with scaly buds, which are divided by function and degree of differentiation into flower buds、leaf buds、latentbuds and adventitious buds, 4 types。
Among them, the peony's flower bud is a mixed bud and can sprout branches、grow leaves、and bloom。Those borne atthe top of the branch are called“terminal flower buds”After a branch has flowered once, the flower stemdries up and retracts by 1 segment on its own。Flower buds borne in the leaf axils of the lower part of the withered flower stem are called“axillary flower buds”or“lateral flower buds”。
Leaf buds only sprout branches and grow leaves, mostly borne in the leaf axils below the flower buds, and some areborne at the top of branches; they are smaller and thinner than flower buds and develop into branches after sprouting。
Latent buds are borne at the lowest part of new branches and are shrunken and small。They normally do not sprout, and only afterflower buds、leaf buds, or branches are injured can they sprout. Their lifespan is relatively long, and they can last 10～15 years。
Buds borne at the root crown are called“adventitious buds”。After emerging from the soil they grow into suckeringbranches, commonly known as“soil buds”。Adventitious buds have especially strong sprouting ability and are the main source for scions、renewing old branches (shoots)and increasing new branches。Adventitious buds do not bloom in the same year; in vigorous ones, atthe top, flower buds can develop and differentiate in the same year and bloom the following year。
The cyclical changes of the peony can be divided according to activity patterns into 2 differentperiods, namely the growth and development period (including reproduction) and the relative dormant period。The growth and development period isfrom the sprouting of scaly buds in February each spring to the withering and falling of leaves at the end of October;the relative dormant period is from the time the leaves wither to the sprouting of buds the following spring。
3 Dormant-period pruning of peonies
Some materials believe that peony pruning is mainly carried out during thegrowth and development period in spring when peonies begin to sprout, but through the biological characteristics of peonies, the author found thatit is better to focus peony pruning work in the dormant period after peony leaves fall in autumn。In spring, only 1 round of bud thinning、and removal of soil buds is needed to achieve plant sturdiness、and nutrientconcentration。
3.1 Significance of pruning
The most important thing in ornamental peonies is to highlight the ornamental characteristics of the peony and, as much as possible, achieve large flowersand bright colors。However, a single peony can provide limited nutrients, and the new year'sgrowth of suckering shoots consumes many nutrients from the plant, causing old branches to lack nutrient supply and retract,and it can also affect ventilation and light penetration、and flowering。Removing the previous year's dead branches and fallen leaves can reducethe loss of plant nutrients, ensure a perfect plant shape and vigorous growth; at the same time improve ventilationconditions and prevent and control the occurrence of pests and diseases
3.2 Pruning methods
Before pruning, observe first. Observe the peony's branch type and growth state, and roughly determine thepositions and types of branches to be pruned。
The peony has the habit of withered tips and branch retreat, as the saying goes:“"The peony grows one chi and retreats eight cun"”whichrefers to this. Because the part of the current-year branch above each leaf axil without bud points cannotlignify and has poor cold resistance, it dies back on its own when winter comes, leaving only the lower half to overwinter;this part is the peony branch's actual growth increment for the year。In late October, thegrowth vigor of the branches has been determined, and targeted pruning is needed。During the pruning process, removepeony dead branches, with special attention to removing excess internal dead branches and excess branches (overdense branches、twin branches、crossing branches、inward-facing branches and diseased or pest-infested branches, etc.), creating good ventilation conditionsand preventing and controlling the occurrence of pests and diseases。In addition, prune off all leaves, but 5 cm of leafstalks can be retained to protect the scaly buds。
Peony flower bud differentiation begins in early to mid-June and ends in late September～to mid-October. Pruning at this time allows flower buds and branches to be selected and retained according to ornamental needsthe number。Ornamental tree peonies require robust plants、with large, brightly colored flowers, so excessiveflower buds should be thinned out. If multiple flower buds are borne on 1 branch, the nutrients cannotbe supplied in a concentrated way when blooming, and the effect of every flower being large and brightly colored cannot be achieved。When pruning, follow“the"remove the middle of three" principle”when there are 3 side branches on the same 1 branch, and these 3 side branches are compared with one anotherif they are dense or crossing, remove the middle branch。Then, according to the differencesamong tree peony cultivars, keep 1～to 3 flower buds on each branch。to ensure that each flower can reachthe expected ornamental effect when blooming。At the same time, all leaf buds other than flower buds should be removed、as well as dormantbuds and adventitious buds, to ensure the nutrient supply for flowering branches。
Current-year basal shoots can be selectively retained as appropriate according to the needs of the plant shape. As the proverbsays“"Peonies need their heads combed, tree peonies need their feet washed"”, clear away excess basal shoots and remove them flush with the root (flatcut)。so as to avoid wasting the plant's own nutrients by pruning after sprouting in spring。Be sure to control the number of brancheswhile also ensuring branch quality. A few branches may be retained for use as renewal branches or for correcting the crown shapebut the remaining branches must be cut off flush with the roots, and do not be soft-hearted。After the initial pruning is completed, check the form of the pruned tree peony、and whether the retained branches are reasonableto ensure the sprouting of buds on the selected retained branches and normal flowering, and pruning can be further improved。