1 seed that you plant might not make it to fruition. Plant zucchini in full sun in compost rich, well-drained soil. Allow the zucchini to continue growing on the plant until the fruits become large and the skin hardens. Prepare a spot in your garden with full sun and rich, loamy soil. These big, fast-growing plants need plenty of moisture and lots of food. Zucchini grow best with a lot of direct sunlight. Seeds should sprout in 7-14 days. Zucchini plants (Cucurbita pepo), those prolific producers of summer squash, grow most readily from seed sown directly in the garden. Zucchini loves warm weather. Growing Ideal pH: 6.0-6.8. Place the seeds about 1 ⁄ 2 inch (1.3 cm) down inside of the soil and cover them up. You can mix organic compost into your soil to help your zucchini grow. Plant 2 seeds in the hole and cover with 1 ⁄ 2 inch (1.3 cm) of soil. Starting Sow seeds 2cm (1″) deep. Aim to space zucchinis no less than 45-60cm (18-24″) apart in rows 90-120cm (36-48″) apart. Zucchini likes to get its start in the spot where it will grow, but if you want to get a jump on the season, start seed indoors 3 to 4 weeks before the last expected frost in 4-inch biodegradable pots (that can be set directly in the ground at planting time so that the roots are not disturbed). Sow 3 seeds in each spot you want a plant to grow and thin to the strongest one. Growing conditions. Wait to plant seeds or transplants until the soil is at least 65 to 70 degrees. In warmer growing zones (including the Southeast, Gulf Coast, and Desert Southwest), gardeners can plant two crops of zucchini, one in the spring and one in the fall. Plant 2 seeds to ensure that you get at least 1 zucchini plant to grow.