Does potted watermelon require manual pollination?
The trend of growing watermelon on urban balconies is gradually gaining popularity, but many growers find it difficult to get fruit despite the lush growth. The core issue lies in the limited pollination mechanism of potted watermelon, especially the lack of natural pollination media in enclosed balconies. This article will delve into the necessity of manual pollination and provide two verified effective methods.
The principle of manual pollination for potted watermelon
Watermelon is a plant with separate male and female flowers, relying on insects and wind for pollination in natural conditions. The enclosed balcony environment lacks wind speed and isolates pollinating insects like bees, preventing the stigma of the female flowers from coming into contact with the pollen from the male flowers, which is the core reason for the failure of fruit setting in potted watermelon.
The golden time window for pollination
The male flowers have the highest pollen activity between 6-9 am, and the best pollination period for female flowers is within 2 hours after blooming. It is recommended to operate in the morning on sunny days, as the flowers are fully open and the stigma secretes sticky fluid, making it easier to adhere to pollen.
Comparison of manual pollination methods
Method 1: Direct pollination with flower instruments
Pick a fully bloomed male flower, remove the petals, and gently touch the stigma of the female flower 3-5 times. The key is to ensure that the anther of the male flower is fully in contact with the three-lobed stigma of the female flower, with this method the pollen utilization rate reaches over 90%.
Method 2: Tool-assisted pollination technique
Use a sterile cotton swab or makeup brush to collect pollen from 3-4 male flowers first, then evenly apply it to the stigma of the female flower in a circular motion. The advantage is that it allows for multiple补充 pollinations, especially suitable for plants with fewer male flowers.
Key details to improve success rate
1. Identify flower types: Female flowers have a miniature fruit at the base, while male flowers only have thin and long peduncles. 2. Pollen preservation: Unused pollen can be stored in a sealed bag in the refrigerator for 3 days. 3. Supplemental pollination skills: Repeating pollination for 3 consecutive days can increase the fruit setting rate by 27%. 4. Environmental control: Maintaining a temperature of 25-30°C and a humidity of 60% after pollination promotes fertilization.
Mastering these techniques can achieve an fruiting rate of over 85% for balcony watermelon. It is recommended to complement with vibration assistance (gently tapping the flower stem daily during the blooming period) and the addition of phosphorus and potassium fertilizers, which can result in a high yield of 3-5 quality watermelons per plant.