When to Sow: April-May Maturity: July-September
Germination: 7-10 days Full Sun
Like all squash, courgettes are heavy feeders and benefit from being planted in areas that have been augmented with lots of compost and well-rotted manure.
Starting Indoors: Sow 2-3 seeds in 2" modules 3 weeks before transplanting outdoors (peat or cardboard containers are ideal). Be careful not to over water, as squash seeds are quick to rot in overly moist, airless compost or soil.
Thin to strongest 1-2 plants per module. Harden off gradually and transplant outside after all danger or frost has passed and the weather is warm and settled. (In most climates this is towards the end of May.) Squash has a very tender rooting system so be extra careful not to disturb.
Plant 1m square (3’ sq.)
Direct Seed: Sow in late spring when the soil has warmed to around 70°F (21°C) and the danger of frost has passed. Sow 1-2 seeds 1m square (3’ sq.) apart and 1/2-1" deep. Thin to 1 plant per spot.
For best results, plant at the top of a shallow mound. As the squash grows it will produce a mass of white roots on the surface of the soil. Cover these with compost or well-rotten manure as they appear.
Maintenance
Keep courgette plants well watered at every stage of their development. Water is especially essential when the plants are in flower and when the fruits have started to swell. Lack of consistent watering can lead to blossom end rot. If you wind up with blossom end rot, remove affected fruit immediately.
Courgettes are heavy feeders and can enjoy up to weekly feedings of liquid seaweed or other similar fertilizers. Mulch well to discourage weeds and conserve water.
Harvesting
Harvest fruits when they reach somewhere around 10cm (4”) long. Although you can twist them off, it’s often easier to cut them off at the base. Just be careful not to accidentally cut into the other parts of the plant (easier to do than one might think!).
Pick fruits regularly (about 3x a week) at the height of the season to keep the plants producing. Best eaten fresh.
Companion Planting
Courgettes do well with all nitrogen-fixers like beans and peas and can be planted alongside corn and benefit from ice radishes, nasturtiums, and borage.