Family: Cucurbitaceae (Squash)

Species: Citrullus ianatus

Annual vine

Conditions: Very rich soil, soil temperature above 65°F (18°C).  Day temperatures in the 80s°F (high 20s°C), night temperatures above 60°F (16°C).  Lots of sun, and sheltered from wind.  Consistent moisture.

Calendar for Hardiness 6B

April – August

Cooking:  Available at the supermarket.


Starting:  Start indoors in paper pots filled with growing soil in mid-April, and keep in a sunny, warm spot for 4-6 weeks.

Transplanting: In mid-May, cover the soil outside with black plastic two weeks before transplanting, to warm up the soil.  When the above conditions are met, cut an X in the black plastic to create an opening for the seedling, water and add some sheep manure or compost.  Rip paper pot, trying not to disturb roots.  Position with soil line similar or slightly higher than in pot, gently pressing around the seedling to avoid air pockets.  Water without getting vine wet.  Place seedlings 2-3 feet (60-90 cm) apart.  Place a cloche over each seedling, or tent with a row cover.

Growing: Ventilate the cover during warm days, and remove once the plant starts to bloom, to allow pollination.  Water when soil gets dry 1/2” (1.25 cm) from the surface.  Leave black plastic in place throughout the entire growing season, to keep the soil warm, and protect the vines from weeds and slugs.

Late August – September

Cooking:  Fresh from the garden or Canadian grown at markets


Harvesting: Wait until the spot resting on the ground turns yellow, and the tendrils near the stem are brown and dry. Cut stem with knife.

Caring:  Continue to care for the vines.

October – March

Cooking:  Available at supermarkets


Saving seed:  For open pollinated varieties.

Pull vines and roots, flatten soil and mulch.

watermelon seeds logoVariety Suggestions:

Sugar Baby from OSC catalogue – 2018.  Description:  Sugar Baby, 75 days to maturity from transplanting day.  Grows up to 8″ (20 cm) in diameter and 5-9 lb (4-5 kg) in weight.




Notes: Timing depends greatly on hardiness zone, but also on specific conditions in the particular spot (micro-climate) the watermelons are growing.  A sunny spot facing South, sheltered by a fence behind, might make a big difference.

Recipes: Carving, Pico de Gallo Salad, Smoothie