Determining whether or not watermelon has been pollinated can be tricky. The only true way to know if a watermelon is pollinated is when you see a baby watermelon forming at the base of the flower. There are telltale signs early on, such as the presence of swelling at the base of the pistil and the formation of a germ tube. Let’s dive into how to identify these signs that your watermelon vine is properly pollinated.
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3 Ways to Know if Watermelon is Pollinated
Wind, insects, birds, and bats can pollinate a watermelon, but you may be wondering how to tell if pollination has occurred. Below are three signs that will help you determine if a watermelon has been pollinated:
Growth of a Germ Tube
A germ tube will grow down the length of the plant’s pistil if pollination takes place. This is so the ovum can be fertilized by the male flower’s pollen. If the germ tubes do not fully mature, this means that the pollination will not be successful.
- If pollination occurs, a germ tube will grow along the length of the pistil.
- If the tube fails to mature, the pollination will fail.
- This sign can be hard to identify, so it’s best left to the experts.
Unfortunately, it can be difficult for someone who is not an expert to tell the difference between a pollinated and unpollinated flower by looking for a germ tube. So, this is not the most reliable way to determine whether or not your watermelon flower is growing fruit.
Swelling at the Base of the Pistil
Male watermelon flowers produce pollen, and female watermelon flowers produce fruit. At the base of the female flower’s pistil, the ovary will form fruit when the plant has been pollinated. This is often the first true sign that your watermelon flower is going to turn into a melon.
- Fruit will begin forming at the base of the female watermelon’s flower pistil if it has been pollinated.
- The fruit will first appear as a small swelling at the base of the flower.
- All female flowers have this small swelling at the base. Once it has been pollinated, you’ll notice the swelling has begun to grow.
The pollen must be transferred from the male flower to the female flower for pollination to occur. If this has occurred and it was pollinated successfully, you will notice small swelling at the pistil’s base. You can encourage pollinators—such as bees—to visit your yard by growing several flowering plants. This will increase the odds that your watermelon flowers become fruit.
Appearance of Mature Watermelons
The only foolproof way to know if a watermelon has been pollinated is when it bears fruit. Once pollinated, mature fruit will appear within 4 months. If you are growing your watermelon inside a greenhouse or polytunnel, however, you can substantially reduce this timeframe, sometimes by up to two months.
- The production of fruit is the only failsafe way to know if a watermelon plant was pollinated.
- Once the flower has begun to shrivel and the bulge at the base of the flower has started to swell, you’ll know for sure your watermelon is pollinated.
- Using a polytunnel or greenhouse can decrease the time between pollination and the appearance of fruit.
Ultimately, however, appropriate watering and warm temperatures are all that is needed for the development of watermelon fruit if the plant has been successfully pollinated. Follow our complete watermelon watering guide to grow the best fruit.
How Long Does it Take for Watermelon to Pollinate?
Watermelon flowers cannot be pollinated until the flowers have fully matured and opened. This may take 4–8 weeks after planting. Once the flowers open, they’re ready for pollination. If you have a view of your watermelons growing in a raised bed, you may even be able to spot hummingbirds or bees visiting your watermelon flowers.
- Watermelons are ready for pollination once the flowers form and are fully open.
- It typically takes 4–8 weeks after planting before watermelon flowers can be pollinated.
- Successful pollination occurs instantly once a pollinator moves from a male flower to a female flower.
If pollination is successful, it occurs instantly. However, that particular aspect cannot really be seen by the naked eye. In some cases, pollen is discharged along the germ tube. Unfortunately, it is usually scattered before it can be observed, so you must be very lucky, and in the right place at the right time to observe this!
What Helps Watermelon Pollinate?
Sometimes wind alone is enough for watermelon to pollinate, but insects help the process along considerably. Bats and birds can also do an excellent job taking pollen from the male plants to the female plants. However, bees and wasps are the best helpers for the job. If such insects are not found on your property in abundance, you can acquire them from a farm and release them near your watermelon plants, where they will quickly go to work.
- Wind can help watermelon to pollinate.
- Bats, birds, and insects can aid in the pollination process.
- You can acquire your own bees to quickly pollinate your watermelon patch.
It’s important to understand that watermelon flowers are only in bloom for a few days, though, so acquire your bees with the right timing in mind. For the average garden, just a few bees is probably sufficient.
How Can You Tell if a Watermelon Has Been Pollinated?
Like many plants in the melon family, watermelons can’t grow to maturity and produce tasty fruit if they’re not pollinated. Here are the key facts about watermelon pollination:
- Watermelon vines produce both male and female flowers.
- Pollen from the male flowers must reach the flowers of the female plants for pollination to occur.
- The presence of swelling at the pistil’s base is a telltale sign that pollination has occurred.
- A germ tube will grow after pollination.
- If the germ tube fails to mature, the pollination will fail.
- The only failsafe way to determine if a watermelon has been pollinated is if the swelling at the base of a female flower begins to grow into a fruit.
Although it can be hard to tell early on if a watermelon flower has been pollinated, it’s a good idea to keep an eye on any flowers with a swelling at the base. These are the female flowers that are capable of producing fruit. Once the swelling at the base begins to grow larger, you’ll know that flower is transforming into a delicious watermelon.