Zucchini is a type of squash, more specifically it is a summer squash. Summer squash takes roughly half the time that winter squash does to mature, 55 - 80 days depending on the variety and growing conditions [See: Difference between Summer and Winter Squash]. Zucchini is very popular not only in the culinary realm, but amongst gardeners as well. It is very easy to plant and grow and under the right conditions it produces prolifically right through early Autumn.
I prefer to plant Zucchini in clusters on small mounds. They can be direct seeded or started indoors in pots, in either event you'll have to wait till the danger of frost has passed. If starting from seedlings it is advisable that you harden them off first. Seedlings should be started indoors four to six weeks before the last frost date.
The mounds should be 8 - 12 inches high and no more 2 - 2.5 feet wide. The plants are best arranged in a circle on the top of the mound with 4 - 6 plants per mound. It may be necessary to thin them at at a later date.
If you only plan on growing a few plants they can also be planted individually without using a mound, either directly from seeds or transplants. Starting from seed they can be direct seeded in the garden in early Spring, after the last frost date has passed. Plant 2 seeds per inch deep hole roughly 3 feet apart. Once they have sprouted and have produced their first true leaves they can be thinned out to the best and healthiest seedling from each planting hole.
Although the best time to plant is early spring - quick maturing varieties can be planted through July in most areas. Unlike winter squash Zucchini can be harvested before the rind hardens and the fruit fully matures, a decent harvest can be attained before winter arrives. The best tasting Zucchini is harvested within a week of flowering. Over-ripe zucchini is lower quality and at times bitter.
Once you have established seedlings growing, mulching lightly is a good idea. Mulch helps to retain moisture in the soil and protects young plants from wild temperature fluctuations. Squash foliage actually creates a sort of living mulch with its broad and imposing leaves once it matures so a heavy mulch of the seedlings is not necessary.
Soil - Well drained
Spacing 2.5 - 3 feet apart - planting a tad closer is not the end of the world, just not optimal.
Zucchini produces male and female flowers. Male flowers are the first to appear followed a week or two later by the females. The female flowers have a small embryonic squash just below the blossoms. After the pollinating period male flowers generally drop from the plant while the females go on to become Zucchini.
Keep the ground uniformly moist, water deeply during dry spells. Water the base, the roots not so much the foliage if at all possible. Excess moisture of the leaves is an open invitation to mildew. Drip irrigation can minimize the amount of foliage and fruit disease compared with overhead irrigation.
The first fertilizer , while the plant is still a seedling should be high in phosphorous for root growth. Excessive phosphorus for too long can lead to premature flowering, a weaker plant later and a smaller harvest, so after cut back on the phosphorous after the first application.
The second fertilizer application, once the plants are solidly rooted - generally about a month into the growth cycle should consist of balanced formula that is higher in nitrogen than phosphorous. Nitrogen is represented by the first number on a fertilizer label [NPK].
Subsequent fertilizer applications, especially prior to fruit setting should have a higher potassium formulation for development of the set fruit. Potassium is represented by the third number on a fertilizer label.
Avoid planting in proximity to, or in the same plot that Potatoes have recently grown - recent being the last several seasons. If feasible, don't plant squash, cucumbers or pumpkin on the same plot more often than once in a three year cycle.
Not all zucchinis are the elongated dark green or cylindrical shapes we are accustomed to. There are varieties in varying colors and shapes bred for any number of reasons. Maturity, yield and so forth vary among cultivars.