- 1). Determine what USDA Hardiness Zone you live in by consulting the map found on the National Arboretum website.
- 2). Plant Mexican marigold in full sun after the last frost, ideally from seedlings or cuttings. The marigold can be grown from seed, but the long growing time before it blooms makes this difficult in regions north of zone eight. Seeds should be planted to a depth of one inch, while cuttings should be buried vertically to half their height with the buds upward. Most soil types are suitable, though rich, well drained soil is ideal.
- 3). Water the marigolds fairly regularly, but don't obsess over it -- Mexican marigolds can survive dry climates. Do not fertilize. Harvest the leaves a few at a time once the plant has reached nearly full size, toward the middle of summer.
- 4). Mulch the plants heavily over winter if you live in zone eight or nine. Pot the marigolds and bring them inside if you live in a zone farther north, or allow them to die and plant again in the spring.
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