Loofah gourds are tropical plants that need plenty of warmth to grow. In Quebec, it is best to start seeds indoors about 4 to 6 weeks before the expected last frost, generally in April. Transplant them outdoors after the last frost, once the soil is thoroughly warm, generally in late May or early June.

They prefer well-drained soil rich in organic matter, with a neutral to slightly alkaline pH. Before planting, work compost into the soil to improve fertility.

Space plants about 1 metre (3 feet) apart. These plants are vigorous climbers and need plenty of room to develop.

They need a full-sun location to grow well. Make sure they receive at least 6 to 8 hours of direct sunlight each day.

Water regularly to keep the soil evenly moist, but avoid standing water. Mulch around the plants to help retain moisture and control weeds.

Fertilize loofah gourd plants with an organic fertilizer rich in potassium and phosphorus to encourage flowering and fruit production.

Check the plants regularly for signs of disease or insects. Loofah gourds are climbers, so provide them with a trellis or another structure to climb.

Loofah gourds are generally ready to harvest about 4 months after planting, when the skin begins to turn yellow and the gourds feel light. To use them as sponges, leave the gourds to mature on the vine until they are brown and dry.