CATDOLL : CATDOLL: What is the most effective way to get rid of red spider mites on gardenias?

What is the most effective way to get rid of red spider mites on gardenias?

Gardenia is prone to insect damage and sooty mold in winter when indoor ventilation is poor and the temperature and humidity are too high.

Prevention and control methods: You can use No. 20 petroleum emulsion and 200 times water for spraying. For soot disease, you can scrub with clean water or spray with 1000 times dilution of carbendazim for prevention and control.

The pests that harm gardenias include aphids, flea beetles and hawk moth larvae. The first two can be treated with dimethoate and trichlorfon, and the latter can be controlled with 666 powder or captured manually.

3. Control of gardenia diseases and pests

(1) Pests

Gardenia is easily harmed by scale insects in an environment with high humidity and poor ventilation. It can be promptly removed with a small brush or sprayed with 100-150 times of No. 20 gasoline emulsion.

(2) Diseases

① Sooty mold: It occurs on branches and leaves. Once discovered, you can scrub them with clean water, or spray 0.3 degrees Baume lime sulfur mixture or 1000-1200 times carbendazim.

② Rot disease: It often occurs on the lower main trunk, causing the stem to swell and crack. Once discovered, scrape it off immediately or apply 5-10 degrees of lime sulfur mixture. It will take several times to be effective.

Leaf spot and chlorosis are common diseases and insect pests. For leaf spot, spray 65% ​​mancozeb wettable powder at 600 times dilution, and add 0.1% ferrous sulfate solution to water regularly to prevent and control chlorosis. Pests include spiny moths, scale insects and whiteflies. Spray spiny moths with 3000 times dilution of 2.5% dimethoate EC, and spray scale insects and whiteflies with 1500 times dilution of 40% omethoate EC.

How to grow gardenia well

How to grow gardenia

1. Soil: It is advisable to use fertile acidic soil rich in humus, which is the key to successful planting in northern families. Generally, you can choose leaf mold and 1 part of decomposed bean cake fertilizer, and add a certain amount of ferrous sulfate, or use 0.2% ferrous sulfate or alum fertilizer water to drench it 3 to 5 times after potting.

2. Cultivation: When planting with cuttings and layering seedlings, ensure that the root system of the plant is fully stretched, and fill the gaps in the root system with fine soil. The density of the filled soil is about 85%, and it is important to tighten the bottom and loosen the top, with a depth of about 1 cm above the root system. Water thoroughly after planting, generally it is better to let water seep from the bottom of the pot.

3. Gardenia requires a high air humidity. Families in the north can put clean water in the pot mat and place a thin board (about 3 cm). The water in the pot should not cover the thin board. The flower pot can be placed on the thin board. Pay attention to adding water frequently. The principle of watering is to water thoroughly when the soil is dry. It is better to use rainwater, snow water or fermented rice water for watering. If it is tap water, it should be left for 2 to 3 days before use. During the growing season, water with 0.2% ferrous sulfate water or alum fertilizer water once every 7 to 10 days. Gardenia should be placed in a place with scattered light under the shade of trees in summer. Water and spray water on the leaves frequently in spring, summer and early autumn to increase humidity. In winter, it is better to place it in the sun, stop fertilizing, and not water too much. You can often use water close to room temperature to flush the branches and leaves to keep the leaves clean, especially in rooms with heating in the north. Do not put the flower pot in front of the radiator or air conditioner to avoid dehydration of the leaves.

4.: Gardenia is prone to scale insects, spider mites and sooty mold in summer when the temperature is high and ventilation is poor. You can spray 40% dimethoate EC at a 1000-fold dilution to prevent scale insects, and 40% trichlorfon EC at a 1000-1500-fold dilution to prevent spider mites. It can also reduce the occurrence of sooty mold. For safety reasons, families can spray with laundry detergent liquid, which also has a certain effect.

5. Repotting: Generally, repotting is done once every 1 to 2 years, preferably in spring. In order to effectively prevent the soil from becoming alkaline, repotting can be done once a year. Before repotting, the pot must be removed. This should be done when the pot is dry and slightly loose. Generally, watering can be stopped for about 10 days. When repotting, cut off some roots, such as diseased and insect-infested roots, and overgrown roots, before planting.

6.: Generally carried out in spring, cut off the overly long branches, weak branches and other branches that affect the plant shape to maintain the beautiful plant shape. Gardenia flowers bloom on the top, so it is appropriate to top-trim during the growing season to promote the growth of flower branches and increase the number of flowers.

Gardenia can be planted in spring, summer and autumn, but the survival rate of cuttings is higher in spring from March to April. When cutting, cut 1 to 2 year old branches from healthy mother plants, cut into cuttings of about 20 cm, each section should have more than 3 nodes, cut off the lower leaves and then quickly dip the lower cut into 500ppm rooting powder solution for 15 seconds, take out and dry the solution and then plant. Before planting, draw lines and dot at a row spacing of 10 cm × 7 cm on the trimmed seedbed, and punch holes on the points with a small wooden stick, then insert 2/3 of the cuttings into the holes, compact with surrounding soil and water to keep them moist, weed and fertilize after survival, and plant out when the seedlings grow to about 50 cm.

Fertilization Gardenia is not a flower that likes fertilizer very much, but because it grows vigorously and is limited by the nutrients in the potting soil, it needs to be supplemented with fertilizers reasonably during the growing period. Apply decomposed human feces or cake fertilizer every 10 days or so. Stop watering one day before fertilization and water thoroughly on the day of fertilization. Stop fertilizing from mid-September. For adult plants, apply sesame paste residue once in mid-June and mid-August, 0.5-1 liang each time, crush and mix thoroughly with the topsoil.

Watering Gardenia likes a lot of water, some people call it "water gardenia". In the north, due to the strong winds, dry air and little rainfall in spring, water it once every three days, and sprinkle water around the potted flowers every morning and evening to increase the air humidity. In summer, the weather is hot after the beginning of the dog days, so water less in the morning and water thoroughly after 2 pm. It is better to irrigate with soft water in summer, because hard water contains more calcium and magnesium salts, which is very unfavorable to the growth of gardenia. At the least, the branches and leaves will turn yellow, and at the worst, they will die quickly. In order to overcome the alkalinity of the soil and water, water it with alum fertilizer water once a week during the growing season to keep the branches and leaves of the vibrator flower green. Watering should be controlled in winter. Do not water unless the soil is dry. Excessive water content for a long time can easily cause root rot and death.

Pests and diseases Gardenias are often prone to chlorosis, a disease in which the leaves turn yellow. Chlorosis is caused by a variety of reasons, so different measures must be taken to prevent and control it. Chlorosis caused by lack of fertilizer: This chlorosis starts from the old leaves at the bottom of the plant and gradually spreads to the new leaves. Nitrogen deficiency: The leaves turn yellow, and the new leaves are small and brittle. Potassium deficiency: The old leaves turn from green to brown. Phosphorus deficiency: The old leaves turn purple or dark red. For the above situations, you can force the application of decomposed human feces or cake fertilizer.

During the growth process of gardenia, the leaves often turn yellow, which is mostly caused by improper cultivation and management. Too much or too little water, too strong or too weak sunlight, too much or too little fertilizer can all cause the leaves to turn yellow, but the yellowing situation is different, and the cause should be carefully observed and analyzed and corrected.

The young leaves of water yellow are dark yellow and dull, the old leaves have no obvious changes, the branches are thin and yellow-green, and the new shoots are shrunken and not growing, indicating that the watering is too much. Remove the flowers from the pot and place them in a ventilated and cool place to dry the soil before putting them back into the pot.

Yellowing due to lack of water is different from yellowing due to too much water. Yellowing due to lack of water means the tips or edges of the leaves become dry and withered, and the old leaves wither and fall off from the bottom to the top, but the new leaves grow normally. Pay attention to watering enough and thoroughly.

Strong sunlight directly hitting some shade-loving flowers (such as spider plants and hostas) can easily cause the tips and edges of the leaves to dry out, and yellow spots to appear on the sunny side of the leaves. Just move them to a shady place.

Yellowing due to lack of light: If the plant is placed in a shaded environment for a long time, the leaves will not get enough sunlight and cannot form chlorophyll. The entire plant's leaves will turn yellow and then fall off. Supplementary light can avoid this disease.

Yellowing of flowers caused by excessive fertilizer or excessive concentration is manifested by dry brown on the tips of new leaves, thick and dull leaves, uneven and unsmooth, and old leaves scorched and falling off. Stop fertilizing immediately, and wash away some of the fertilizer with a large amount of washing in severe cases.

The yellowing caused by lack of fertilizer is manifested in the color of young leaves becoming lighter, yellow or light green, while the old leaves are relatively normal or gradually turn from green to yellow. Check the potting soil, if there is dryness, the soil should be replaced, and thin fertilizers should be applied frequently and some alum water should be poured in time.

Cultivation of Gardenia

1. Soil: Gardenia is an indicator plant of acidic soil, so the slightly acidic soil environment is the key to determining the growth of gardenia. The culture soil should be a mixture of 70% slightly acidic sandy loam and 30% leaf humus. The soil pH should be controlled between 4.0-6.5.

2. Temperature: The best growth temperature for gardenia is 16℃-18℃. Too low temperature and direct sunlight are extremely detrimental to its growth. Therefore, in summer, it is advisable to place gardenia in a well-ventilated, humid and light-permeable sparse forest or shade shed for maintenance. In winter, place it in a sunny environment with a temperature not lower than 0℃ to let it dormant. Too high temperature will affect its flowering next year.

3. Water: Gardenia likes humid air, so watering should be increased appropriately during the growing season. Usually, watering can be done when the pot soil turns white, and water thoroughly at one time. In the hot summer, spray the leaves 2-3 times a day to increase air humidity and help cool the plant. However, after the flowers bud, watering should not be too much to avoid causing buds to fall off. In winter, watering should be kept dry to prevent excessive waterlogging from rotting the roots.

4. Fertilizer: Gardenia is a plant that likes fertilizer. In order to meet its fertilizer needs during the growth period and maintain the slightly acidic environment of the soil, ferrous sulfate can be mixed into the fertilizer solution for fermentation in advance. After entering the peak growth season in April, topdressing can be done once every half a month (it is best to add more water when fertilizing to prevent burning of the flowers). This can not only meet the fertilizer needs of gardenia, but also maintain the soil environment in a relatively balanced slightly acidic environment to prevent the occurrence of chlorosis, and at the same time avoid the damage to gardenia caused by sudden supplementation of ferrous sulfate and local over-acidity.

Here are some tips for growing gardenias:

1. Gardenia needs sufficient sunlight, because gardenia is a plant that needs sunlight very much. Both the healthy growth of its leaves and the opening of its flowers require the assistance of sunlight.

2. Gardenia is a flower that loves water very much. It is also called "water gardenia". It must not be allowed to suffer from excessive water shortage during maintenance.

3. Open windows more often for ventilation. Air permeability is very important. Spray fungicides and insecticides every half a month or so to prevent diseases and pests.

The potting soil should be transparent: Mix leaf mold, garden soil and river sand to make the culture soil. Temperature requirements: Keep it indoors in mid-October and keep the room temperature above 5 degrees. Watering method: Water the gardenia once every 5-7 days in winter and 1-2 times a day in summer. Scientific fertilization: Apply cake fertilizer water once every 10 days during the growth period of the gardenia.

If the room temperature is above 15°C, you should open the south-facing windows and doors, ventilate properly, and lower the temperature. Otherwise, it will easily cause germination, and it will be harmed by low temperatures, which is extremely unfavorable for its growth and flowering the following year. 3. Light. Gardenia likes sufficient light, especially in spring and autumn. It should be given more than 8 hours of sunshine every day, otherwise it will be detrimental to its growth and development and wintering. Avoid strong sunlight exposure at noon in summer, otherwise it will turn the leaves yellow. It should be placed in a diffuse light place for maintenance, and the light transmittance should be 40-50%. Place it indoors in direct sunlight facing south in winter.