How do pitcher plants catch insects? Are they harmful to humans, and how to grow them at home
Pitcher plant, also known as water-pitcher plant, monkey water bottle, monkey urn, piglet cage, and forget-sorrow grass, is an annual herb with no bulb, flowering and fruiting throughout the year. So how does the pitcher plant eat insects? Is it harmful to humans? Can it be kept at home? How to grow it? According to data from the Droseraceae family, the pitcher of the pitcher plant contains nectar glands that can secrete nectar to lure insects. After an insect enters the pitcher, the lid of the pitcher does not close, and the inner wall of the pitcher's mouth is very smooth, which prevents the insect from crawling out. The pitcher often contains half a pitcher of water. When there is too much water, the tendril cannot bear the weight and will automatically tilt to pour out part of the water. The inner wall of the lower half of the pitcher is slightly thicker and has many digestive glands. These glands secrete a slightly sticky digestive fluid that is stored at the bottom of the pitcher. The digestive fluid is acidic and has the ability to digest insects.
Is the pitcher plant harmful to humans?
The pitcher plant is harmless to humans. Because people often use pitcher plants to catch some insects, they are often grown outdoors. When an insect approaches, the leaf lobes snap shut, so that the insect cannot move until it dies. Therefore, it can be said that the pitcher plant is harmless to humans, and is instead beneficial.
Can the pitcher plant be kept at home?
The pitcher plant can be grown at home, but the ideal place is on a balcony. Some varieties of carnivorous plants, such as Venus flytraps and pitcher plants, relatively need direct sunlight. So if kept indoors, the Venus flytrap will grow smaller and smaller due to insufficient light, pitcher plants will grow leggy, and red varieties will turn green, and eventually the whole plant will gradually weaken and finally die. So if you want to grow them indoors, you had best first understand the habits of carnivorous plants and the suitable temperatures (for example, the cobra lily, when there is a large temperature difference between day and night, can tolerate about 34 degrees during the day. Without a temperature difference, cooling needs to be considered at 31-2 degrees, while the minimum temperature can absolutely reach below 5 degrees; and the parrot pitcher plant, even without a day-night temperature difference, can reach a maximum temperature of 38 degrees, and its minimum temperature can also reach below 5 degrees). Only in this way will you not kill the plant.
How to grow the pitcher plant?
The suitable growth temperature for pitcher plants is 25~30°C, from March to September it is 21~30°C, and from September to March of the following year it is 18~24°C. In winter the temperature must not be lower than 16°C; below 15°C the plant stops growing, and below 10°C the leaf edges suffer frost damage.
1. Temperature control: When sowing pitcher plants, the minimum temperature is best kept above 15°C, and the minimum overwintering temperature during the growing period must be above 10°C. In northern regions it is advisable to overwinter in a greenhouse to avoid frost damage.
2. Seedling method: Pitcher plants need to be sown and raised in a seedling box or plug tray, and the seedling box or plug tray should be placed in a greenhouse or a small arched shed to increase the germination rate, and it is not suitable to raise seedlings in the open field.
3. Selection and preparation of substrate: The cultivation substrate for pitcher plants should be a relatively loose, fertile substrate with strong water-holding capacity, and commercially available seedling substrate can also be used.
4. Substrate disinfection: When sowing pitcher plants, the substrate should be disinfected to prevent pests and diseases from invading. The substrate should be dried in the sun before use, and after sowing a disinfectant should be used to soak the substrate thoroughly.
5. Sowing method: Because pitcher plant seeds are tiny and inconvenient to handle, it is best to fix the seeds on absorbent paper, one seed per red circle. Before sowing, cut the seeds together with the absorbent paper, hold the absorbent paper with needle-nose pliers, and place it on the surface of the substrate. The sowing rate is preferably 1—2 seeds per cell.
6. Covering: Pitcher plant seeds are photophilic and need appropriate light to germinate better, so there is no need to cover them after sowing.
7. Spraying to retain moisture: After sowing pitcher plants, the substrate should always be kept moist. Water can be sprayed with a fine mist, or water can be soaked up from the bottom of the tray. The water should be disinfected with strong chlorine or Baidusha before use, and the relative humidity should preferably be kept at about 90%.
8. Shading: Pitcher plants are afraid of strong light, and neither after sowing nor during the seedling stage are they suitable for strong light exposure. A shade net needs to be used for shading to benefit the growth of pitcher plants.
9. Emergence: When temperature and humidity are suitable, pitcher plant seedlings can emerge in as fast as about 25 days, and at the slowest they emerge only after two months.
10. Disease prevention at the seedling stage: Pitcher plant seedlings grow relatively slowly, so attention should be paid to preventing pests and diseases. Daily care should pay attention to ventilation and air permeability, prevent rain from falling on them, and 50% carbendazim wettable powder at 800~1000 times can also be sprayed regularly.
11. Transplanting seedlings: Pitcher plant seedlings can generally be transplanted into pots for cultivation after they grow to 5 cm tall. When transplanting, be sure to keep the roots protected, and it is best to plant them a bit deep, burying them 1 cm deeper than the original soil surface each time. It is best to transplant pitcher plants twice before potting them for cultivation. Seedlings cultivated in this way are relatively robust, and their leaves are long and beautiful.