Growing habits:
Nanmu is fond of light and yin. Like warm and humid climate, not tolerant of drought and cold. I like fertile soil. Fast growth, strong germination and strong wind resistance.
We need plenty of sunshine in winter, and we should avoid strong light in summer. We are afraid of dry wind in northern spring and scorching sun in midsummer. It grows best at the temperature of 25℃-30℃ and the relative humidity above 70%. Potting requires loose and fertile culture soil, high humus content and strong drainage and air permeability.
Breeding:
Breeding mode
Breeding in root cutting
1. Selection of mother plants with root cutting ears
Root-ear mother plant is a breeding mother plant that provides high-quality seed strips, and it must be strictly selected to ensure the excellent characteristics of the mother plant. Generally, trees with 5- 10 age are adopted, which is suitable for greening seedlings. They are robust, free from pests and diseases, with dark green leaves, dense branches and good performance.
2. Collection of roots and spikes
April-May every year is a good season for landscaping and the best time for cutting propagation. A large number of green seedlings have left the nursery, so we can take this opportunity to collect the residual roots of the seedlings after digging holes, and we can also dig some roots of Phoebe heterophylla, which are shallow from the soil surface. As a material for cutting propagation.
3. Treatment of roots and ears
The treatment of roots and spikes in asexual propagation is an important link related to the survival and rooting of cuttings. The roots and spikes of Populus heterophylla should be treated in time. The method is as follows: select roots with cross section of 0.8- 1.2Cm, cut about 10cm, arrange them from beginning to end in a bundle of 20-30 roots, put them in a cool and ventilated place to promote the fleshy roots to evaporate too much water to prevent rot, and dry them. Selection of cutting medium and environment of cutting medium adopts screened pure river sand with particle size of 0.5- 1.5. As a cutting substrate, Omm has the advantages of good ventilation and drainage.
4. The structure of the cutting bed
The cutting bed is made of bricks, with a height of 25m and a width of 10Ocm. The length depends on the number of cuttings. The bed bottom is flat, the cutting matrix is increased in the bed, and it can be put into use after being slightly leveled and compacted.
5. Selection of cutting environment
The selection of cutting environment is very important to the survival of cutting. The suitable rooting temperature of Populus heterophylla is 15-25 degrees, the humidity is 70%-80%, the light is sufficient, and the weak shade is better. Choosing the cutting ground set in this humid condition for cutting propagation is easy to form adventitious roots and buds, and the survival rate is high.
When cutting roots, the best cutting method is row cutting, the spacing between plants is 4cm, the row spacing is 6cm, and the slats with the width of 6cm, the length of 100cm and the thickness of 2cm are used as rulers and placed on the sand bed for row spacing. Use a spatula to draw an oblique ditch along the edge of the board, with a depth of about 7cm. It is advisable to insert the cuttings into the sand bed for 2/3, and then put the cuttings neatly into the ditch, with an equal distance of about 4cm.
Sowing propagation
Because the seed coat is solid and the germination rate is low, it is best to break the seed coat before planting to promote its germination. In addition, the planted seedlings are prone to pests and diseases, so the soil used should be strictly disinfected. It is best to use sand bed or the above-mentioned broken shell sowing method to accelerate seed germination and improve seed germination rate, which can germinate in about 30 days.
cutting
Cutting propagation is easy and widely used. Cuttings are usually carried out in spring and summer, but the main branches should be selected as cuttings, and the plants growing with side branches as cuttings are skewed and not straight. The cutting length is 10 ~ 15cm, and it can take root in about 4 months under the conditions of 18℃~ 25℃ and high air humidity. If the base of cuttings is soaked with 200 ppm indolebutyric acid (IBA) for 5 hours before cutting, its early rooting can be promoted.
In order to get more main branches as cuttings, young trees can be cut off, making many upright new buds from the top and cut off as cuttings in spring. After cutting the top, the mother plant can continue to grow terminal buds, which can be used for the permanent reproduction of the mother plant. The soil for potted Phoebe bournei should be composed of 40% peat soil, 40% humus soil and 20% river sand. The basin soil should be kept moist during the growing period. If it is too dry, the lower leaves will droop, but it should be kept slightly dry in winter. The room temperature should be kept above 5% in winter, and the low temperature will freeze the growing point to death.
Seedling transplantation
Phoebe bournei likes warm and humid, tolerant to shade and not cold. Seeded seedlings have long straight roots and few fibrous roots. Seedlings are easy to die after transplantation. In order to improve the survival rate of Populus davidiana seedlings, the following technical points should be paid attention to.
First, root protection
Because the lateral roots of Populus davidiana seedlings are sparse and the hairy roots are thin, if they are not paid attention to, they will shrink and dry up. Therefore, it is very important to protect the root system of seedlings. First of all, it should be transported with soil in pots, and the original culture soil should be kept moist. Secondly, the seedlings should be planted immediately after they are bought back. If it is too late to plant them, they should be placed in a cool and humid place and not exposed to the sun to protect the seedlings, especially the roots. In addition, when the temperature is low in winter, the root system is vulnerable to freezing during transportation, so attention should be paid to heat preservation.
Second, fine planting.
When planting, the seedlings should bring the original soil as much as possible. The soil should be loose and fine, and the root soil should not be too hard. Water the root after planting. In addition, the planted seedlings of Phoebe bournei have long and straight roots, so they should be planted deeply to avoid exposure and lodging, which will affect their survival.
Third, heat preservation
Minnan is not cold-tolerant. If you buy seedlings for planting in winter or early spring, you should pay attention to antifreeze during transportation, and take heat preservation measures after planting, such as planting in a greenhouse or covering them with plastic film arches.
Fourth, shading.
Phoebe bournei is a shade-tolerant flower, and its seedlings are more afraid of sun exposure, so shade should be provided immediately after planting.
5. Seedling cutting treatment
Aralia elata seedling tissue is tender and easy to break, so the following measures can be taken to remedy it. Rooted seedlings can be washed with clean water and then inserted into ordinary sand. After 1-2 weeks at suitable temperature, it can be re-rooted from the cross section and planted after the root system is developed. For seedlings with broken buds, stems and leaves, they can be fixed as usual, and new buds will germinate after a certain period of survival.
Pot management
Loosening and watering
Water and loosen the soil in time after planting to reduce water evaporation. Water moderately at ordinary times, and water frequently during the growing period, 2 ~ 3 times a week, and the infiltration depth is 10 ~ 15 cm. With the growth of seedlings, the number of watering is reduced, and the soil and surrounding environment are often kept moist to prevent drought and flood. In the hot and dry season, we should often spray water or spray the leaves and the surrounding environment to increase the air humidity and keep the soil moist. Avoid too dry soil in summer and too much water in winter. Too dry or too wet can easily cause the lower leaves to droop. Avoid strong light in summer, put it in the shade of the shed, and sprinkle water frequently to keep the air high humidity.
Plastic surgery management
The beauty of Aralia elata lies in its tall and straight posture. In the second year of cutting seedlings, or when the seedlings grow to about 50 cm, they should be supported by vertical sticks to prevent the plants from distorting and affecting the ornamental effect. Young trees should turn pots 1 time every year or the next spring, and plants over five years old should turn pots 1 time every two or three years, and combined with spraying chlormequat chloride, the height of Phoebe bournei should be controlled. In the northern area, leave the room at the end of April or early May to avoid the wind and keep it in a sunny place. Proper shade should be provided in midsummer, and pots should be turned in time during the growing period to prevent trees from growing askew and affecting viewing. Phoebe bournei is cold-tolerant, and the northern area should be moved indoors at the end of September or the beginning of 10 (cold dew), with sufficient sunshine, ventilation, no fertilization and no water control, and the room temperature should not be lower than 8℃.
Diligent fertilization
Potted Phoebe bournei should be mixed with humus soil, peat soil, pure river sand and a small amount of decomposed organic fertilizer. Potted soil should be mixed with 3 parts loam, 1 humus, 1 coarse sand and a small amount of plant ash, and the depth of the soil layer depends on the bud point where the upper roots are just exposed on the soil surface. Because new buds germinate in spring, topdressing with decomposed rare organic liquid fertilizer and calcium fertilizer 1 ~ 2 times a month can keep plants fresh and leaves moist.
The causes of yellowing of Aralia elata leaves can be summarized as follows:
1, the light is too weak. It will grow well if it is maintained in a well-lit place. If it is left in a well-lit place for a long time, its leaves will turn yellow and fall off, so it is best to move it to a well-lit place, otherwise the plant will further aggravate the disease.
2. Water too much. The watering principle of nanmu is that when it is dry, it will be wet. Don't water too much and too often, otherwise the soil in the basin will not be watered, otherwise the roots will rot due to lack of oxygen, and it is difficult to absorb water and nutrients, and the plants will have uncomfortable symptoms.
3, low temperature or high temperature hazards. When the temperature is lower than 5 degrees, the leaves of Aralia elata will turn yellow and fall off a little. If the air humidity is low during high temperature, a large number of yellow leaves will appear.
4. The air humidity is too low or the wind is too strong, which causes the leaves to dehydrate and turn yellow. This needs to be placed in a sheltered place, or sprayed with water frequently to improve the air humidity.
5. Infection of diseases. Generally, carbendazim, chlorothalonil and other drugs should be sprayed for prevention.