Watermelon is North America’s favourite summertime treat! There’s nothing more refreshing than a big slice of cool watermelon on a hot summer day. Low in calories and high in fibre, they’re a perfect choice for watching your weight, and they’re also a great source of Vitamin A, C, and Lycopene. 

When To Plant

Watermelons require a long, warm growing season. These melons thrive in the southern United States but can also be grown in Canada. Your Watermelons will thrive as long as you start them indoors about a month before the planting date. These plants look for temperatures above 27 C during the day and at least 21 C at night and tend to be very sensitive to frost and light freezing. Plan for between 2-5 plants per person depending on their appetites. 

How to Plant

When starting your seeds indoors, use individual peat pots as the root system is too thick to divide before transplant if sown in a flat. When transplanting, place three seedlings on a hill and give it a week. After one week, thin the plants to the two best growers.

When direct sowing your seeds, plant 3-4 seeds in a hill and cover them with a hot cap to keep the pests out, speed up growth, and protect them from frost. Always plant your seeds on a small hill with about 1/2 cup of 5-10-5 fertilizer about three weeks before planting. Once your plants have sprouted at least three true leaves, thin the seedlings to the two strongest.

How to Care

Side shoots are critical with vine plants like these, and when you’ve grown three leaves, be sure to pinch off the growing end to encourage the side shoots. Doing this should produce a new side shoot off of each of the leaves. Once those side shoots have grown three, leaves pinch off the central growing area yet again!

Once your Watermelon vines start producing flowers, be sure to fertilize again with another 1/2 cup of 5-10-5 fertilizer. When the fruit begins to appear, pinch the vine at two leaves beyond the fruit to avoid wasting energy and maximize fruit growth. If you’re growing on a trellis, be sure that your fruit is well supported by netting or elevated from the ground if sprawling in a patch to avoid disease. 

Watermelon vines are heavy feeders, and you guess correctly; they require a lot of moisture. We recommend that you use plastic mulch around the area you intend to grow your watermelons since weeding and cultivating can be a critical issue. Not only does the plastic mulch keep weeds down and water in the soil, but it also will keep the melons off the ground and prevent rotting and disease. Place and anchor the plastic mulch before planting and place a central slit for transplanting and a few extra slits in low spots to allow watering and rainwater to filter through.

How to Harvest

The trickiest part of growing watermelon is knowing when it’s time to harvest. There are several different generally accepted methods of determining whether a watermelon is ripe, and most of them are shenanigans. 

Click Here to Return to the Main Page