Come high cantaloupe season, my late Poppy, Isadore Hirsh, a house call-making doc with a pre-diabetic’s sweet tooth, would come home at midday for his favorite late summer lunch: an entire half a cantaloupe with a scoop of vanilla ice cream in its center cup.

Despite his predilection for sugar (think pie for breakfast), Poppy died just shy of his 95th birthday. His cantaloupe sundae lunches make me feel better about letting his namesake, my fruitarian 3-year-old Theodore Hirsh, gorge himself on ripe local cantaloupe at dinnertime.

After all, this is one of the only times of year I freely indulge in melons (I prefer to buy local). Theo’s economist father, Dan, gets more “utility” from melon than I do – an economic concept that describes how people rationalize their choices if the amount they like something outweighs its cost. So Dan feels less guilty than I about splurging on imported specimens all year and the non-local but still ripe and delicious watermelons that have been plentiful at Shaw’s for the last month. On grocery store trips there and to Hannaford, Dan bribes Theo with plastic cups of cut-up watermelon, available whatever the season. The treat helps him stay put in the shopping cart seat.

Melons, more than just about any other fruit or vegetable, test the locavore credo. Maine summers aren’t hot or long enough to fully swell them with sugars. Committed farmers market shoppers find our frequently bland, watery honeydews, cantaloupes and watermelons can’t hold a candle to the more flavorful, fragrant ones they remember from childhoods in New Jersey or Virginia, let alone Florida or California.

“Are these squash?” some Bowdoin College students recently asked about the huge, dark green Sugar Baby watermelons thriving in a sunny patch on the campus farm. They looked like giant balls of zucchini.

“These are watermelons!?” a surprised student said, spreading compost and peeling cured onions during a recent garden workday. “I have no concept of what grows in Maine.”

Mike Perisho, the Bowdoin Organic Garden assistant, replied that watermelons like Sugar Babies, and cantaloupes he’s tending on his startup farm in Gardiner, can indeed grow here, often helped along by heat-augmenting black plastic mulch. What is rare in Maine, he said, is the seedless, green-striped watermelon so ubiquitous at the grocery store. Perisho said seedless varieties require even more heat, plus, as sterile plants, must be grown in tandem with seeded watermelons whose male flowers provide fertile pollen to set fruit.

Melons ripen in a 12-hour window, often going from underdone to overripe faster than busy farmers can get to them. Theo delighted in foraging for cracked, but still sweet, not yet fermenting, yellow watermelons when we went to dig potatoes at Crystal Spring Farm in Brunswick last September. The farmers were happy to oblige. Perhaps we should instigate melon-gleaning programs – surely good fruit is going to waste. It’s labor-intensive to grow, hardly a cash crop, says Perisho, adding that melons will remain a fun sideline but never a staple of his Gardiner farm.

Few farms here make melons their focus. The University of Maine reported that in 2009 only five certified organic farms in the state had significant melon production. That’s unfortunate, because the melon gene runs deep on both sides of my son’s family tree. Cantaloupe is just about Dan’s favorite fruit – and likewise for his mother, Debbie. After Theo was born, she kept us stocked in those distinctively grooved, sweet Dulcinea Tuscan cantaloupes. They hailed from California, not far from Oregon where we then lived. I didn’t care about their origin anyhow: In my parched, sleep-deprived state, that cantaloupe appealed for breakfast, lunch, even dinner.

A generation before, Debbie earned her reputation as a “healthy” mom for packing cut-up cantaloupe as a summer snack for her kids when they spent the afternoon at the neighborhood pool. When she was growing up, watermelon helped Debbie’s family beat the heat in their Bronx apartment, whenever her father deemed it hot enough to be a “watermelon day.” Then there’s Dan’s great-grandfather, Nate Winkeller, a Jewish immigrant peddler who sold melons at the Boston fruit market at Haymarket – the market still exists today.

My mother is also quite the fruit whisperer. She’s the cantaloupe lady to Theo, since he counts on his “Gima,” as he calls her, to keep her fridge stocked with the orange chunks he covets, regardless of the season. Her signature, instant appetizer is sweet cantaloupe wrapped with salty prosciutto. But she has little love for her native Virginia melons.

“I have never been a fan of local melons,” Mom confessed in an e-mail. “It is rare that I find a really sweet one with deep flavor and not mushy texture.”

Her confession revived a long-running debate with Billy Jenkins, a dear friend and expert (and skilled gardener himself) in the produce department of her local grocery store. Billy has long championed peak-season Virginia melons to her. But my mom, who doesn’t carry the locavore torch quite as high as I do, argues that the California melons are better, even come summer.

What she and Billy do agree on is how to choose a good melon – tips I tried to pass on to Theo when we chose watermelons and cantaloupes out of big crates at our Crystal Spring Farm CSA (Community Supported Agriculture) pickup. Select a melon with:

• A hollowed-out (fallen off) stem, to show it ripened on the vine.

• Flat, yellow spots or dents (ditto the vine-ripening), so heavy with sugary juice it lay flat on the ground.

• Density and heft for its size – such melons tend to be less mealy.

• Aromatic fragrance.

• Yellow instead of green rind between the webbing that’s on some melons.

• Ripe softness. Press against the end to check, watching for mold that indicates it’s overripe.

We should teach our children to waste not, want not with our precious local melons. Roasted, salted watermelon seeds are a popular train snack in China – but I’ve never bothered to roast my own smaller ones here. Nor need cantaloupe seeds be consigned to the compost bin. A recent recipe for Oaxacan horchata from Edible Portland (the one in Oregon) made this case, blending the seeds with blanched almonds, water, sugar, cinnamon and lime for a creamy, refreshing drink. Who knew?

SPICY THAI MELON SOUP

This recipe is inspired by a revelatory raw soup that chef Ko Attebery served at a beer dinner I once attended at Cloud 9 (now Cloud and Kelly’s) in Corvallis, Ore. Since basil, which succumbed to downy mildew, and cilantro were sparse at the Brunswick farmers market, I rounded out a recent batch with mint, pineapple sage, lemon verbena and red shiso from my garden instead, and I garnished the soup with prolific and spicy nasturtium flowers (and their lily pad-like leaves). The recipe calls for Kaffir lime leaves – worth seeking out at Asian markets. If you can’t find them, substitute lime zest, which is less floral. Eliminate the oil if you prefer a leaner soup.

Serves 4 as a starter

1 stalk lemongrass

Juice of 1 lime

5 cups cubed and seeded watermelon or cantaloupe

2 kaffir lime leaves

2 tablespoons grated or minced ginger

1 fresh Thai chile pepper, with seeds to taste

2 tablespoons chopped Thai basil, plus more for garnish

2 tablespoons chopped cilantro, plus more for garnish

1 shallot, minced

Couple dashes fish sauce or salt, to taste

2 tablespoons olive or coconut oil

2 tablespoons chopped salted roasted peanuts, to garnish

2 tablespoons crunchy coconut flakes, to garnish

Remove the woody exterior of the lemongrass and mince the tender interior to get 2 teaspoons.

Place the minced lemongrass and the remaining ingredients (except for the garnishes) in a blender or food processor, and blend/pulse until pureed. Taste and adjust seasonings. Chill the soup at least 1 hour.

Serve cold, garnished with basil, cilantro, peanuts and coconut flakes. For a more substantial soup, add dollops of lime-and-cilantro-marinated crabmeat or lobster.