Growing Guidelines for Greenhouse Growers


In general, all melons need warm weather and cannot tolerate cold conditions. Schedule your crop so that plants will be available once all danger of frost has passed and continue to offer them only when the customer can still get fully mature fruits.

Fast Growing Melons Can Increase Vegetable Sales

There are some vegetables that we in the industry just assume don’t need to be offered as bedding plants. They are more suited to the gardener direct sowing in the garden and are so fast growing that we may not want to attempt growing them. Melons typically fall into this category. However, that doesn’t mean they can’t be grown and offered as bedding plants. In fact, with today’s beginner gardener often being hesitant to try new varieties or different classes, adding a few unique melons to the vegetable starter-plant display is a good way to encourage more sales.

Most melons that are available in seed packets for the home gardener are tried-and-true varieties like heirlooms and open-pollinated choices. This leaves out an entire array of the latest outstanding genetics. Most of today’s high-quality melon hybrids offer superior disease resistances and fruit yields and a wide range of unique sizes, colors and flavors.

Lilliput F1 melon from Sakata Home Grown is a wonderful example. Itis a unique 1-2 pound personal-sized, miniature Eastern melon that offers very high sugars and fragrance that combine for a wonderful flavor. The firm, deep orange flesh is maximized by a small, closed-center cavity. The exterior begins light green, turns to a yellow-tan color as it ripens and then the stem slips when fully mature. It is resistant to fusarium wilt races 0-2 and powdery mildew races 1 and 2. A delicious melon with early to mid-season maturity, it is an ideal choice for the home gardener or any specialty market.

In general, all melons need warm weather and cannot tolerate cold conditions. Schedule your crop so that plants will be available once all danger of frost has passed and continue to offer them only when the customer can still get fully mature fruits (maturities generally range from 80-110 days from seeding).

The keys to growing melons as a bedding plant crop are to sow seed direct into the final container and to keep tightly to the schedule since they are such fast growers. Seeds should be sown 3 per pot in a larger (6-8”) container that can be transplanted directly into the ground. Multiple transplants (whether by the grower from flat to pot or by the gardener from pot to garden) will severely damage the roots and, if the plant survives, the yields.

Below are general growing guidelines:

  • Optimum germination temperature: 70 to 75F (21 to 24C)
  • Optimum growing-on temperature: 65 to 70F (18 to 21C)
  • Crop time: 4-5 weeks (6-8” transplantable pot)

Stage 1: Germination (Days 1-7)

Sow directly into finishing container. Use a well-drained media with a medium initial nutrient charge and a pH between 5.8 and 6.2 and an EC of less than 0.75 mmhos/cm (2:1 extraction). Prior to sowing, water the media to the point of drip. Sow seeds and cover. Keep ammonium levels to less than 10 ppm during germination.

Stage 2: After Stem and cotyledon emergence (Days 8-14)

Maintain soil pH between 5.8 and 6.2 and an EC of less than 0.75 mmhos/cm. Reduce soil temperatures to 65 to 70F (18 to 21C). Also reduce moisture levels. Allow media to dry slightly between irrigations to promote root development. For disease prevention, irrigate early in the day so foliage will fully dry. Begin feeding at 50 to 75 ppm N from a calcium/potassium nitrate based formulation once cotyledons are fully expanded, alternating feed with clear water.

Stage 3: Growing On to Finish (Days 15-35)

After the development of true leaves, maintain day temperatures of 68 to 75F (20 to 24C) and night temperatures of 65 to 70F (18 to 21C. Allow the soil to dry thoroughly between irrigations (while still avoiding severe wilting). Increase feed to 100 to 150 ppm N from a calcium/potassium nitrate based formulation. Fertilize every second or third irrigation, depending on plant performance. In the final stage of production, plants should be monitored closely for stretching. Remember, chemical PGR’s cannot be used on any vegetables or herbs. Plant height can be controlled by withholding fertilizer (particularly phosphorous and ammonium form nitrogen) and by practicing DIF techniques with night versus day temperatures.