VIDEO: The secret to big melons; plastic

RAYMOND, Alta. — What delights the hearts of boys more than a cold slice of watermelon on a hot summer day?

About 20 boys converged on Ron McMullin’s melon patch near this southern Alberta town Sept. 6 to pick and eat some of the fruit they helped plant earlier in the year as part of a Scouts activity.

McMullin, a Scout leader, knows about boys and their taste for the juicy, sweet fruit. His own love of watermelon led him to devise ways to grow them in a climate that doesn’t have the longer season required for optimal melon growth.

“I grew them as a kid. I always wanted to grow them because I loved to eat them. The biggest I ever got when I was young was six or eight inches long.”

McMullin wasn’t willing to leave it at that.

“I was able to work for my brother, who is an inventor, and he let me do what I wanted so I thought, ‘well, why don’t I develop a way to grow watermelons in this area?’ ”

Raymond, Alta., where McMullin grew up and where he now has his melon patch, is in the 4b climate zone. Though melons can be grown in zones three through 11, most of the imports in Canadian grocery stores come from the southern States and further south, where both daytime and nighttime temperatures are much higher and the growing season is longer.

“The secret to growing watermelons here is having heat in May and June. Our summers are good, but May and June are too cold.”

McMullin solved that problem by putting down black plastic with holes made for the plants and for water access. Over that, he drapes six mil clear plastic, held up by four-legged peony rings to keep it off the sprouting plants.

He pins down the plastic with soil around the edges, to keep it in place amid the frequent southern Alberta westerly winds.

He has found that the temperature under the plastic can be 20 degrees C higher than the outside temperature on a sunny day, and soil temperature is 10 degrees higher.

Thus the problem of heat is solved.

He plants the melons from seed sometime after May 10 and depending on summer weather, they are ripe by late August.

He also uses a slow release nitrogen urea but said any general purpose fertilizer with 16 to 20 percent nitrogen, plus phosphorus, would do the job.

A system of drip irrigation rounds out the growing project.

This year McMullin planted 18 different watermelon varieties, along with 20 types of cantaloupe.

Vista is the most productive and consistent watermelon variety he has found so far.

“You often get 18- to 20-pound watermelons using that variety.”

His personal best is a 37-pounder that he grew in 2003.

Other favourite varieties are Crimson Sweet and New Queen, the latter being a smaller orange variety. New Yellow Baby is a yellow type with a fine texture and sweet taste. Jade Star is a dark green variety that ripens earlier than some others.

A cool and often rainy July in the region delayed the melon crop a bit this year, so harvesting took place Sept. 6, much to the delight of McMullin’s scout troop.

Each of them ate watermelon in the field and took at least half a melon home to the family.

The juicy facts:

  • Watermelon is thought to have originated in Africa.
  • It is considered to be both a fruit and a vegetable.
  • More than 1,200 varieties exist.
  • It is rich in lycopene, a carotenoid antioxidant and a source of vitamin C.
  • The rind and seeds are edible.
  • Seedless varieties were developed via hybridization
  • The world record size is 350.5 lb.

Sources:,,, Guinness

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