Answer: You can start zinnia seeds indoors, 6 to 8 weeks before your typical last frost date. But zinnias are among the most forgiving annuals.
Consider starting them indoors now, then planting them out in about a month, or the first week of June. The plants grow so fast once the soil and nights are really warm that you won't really lose much time.
It's also possible to sow zinnias in the garden exactly where you want them to grow. Again, they grow so fast once weather warms that by August in the garden, it would be hard to distinguish zinnias started by seed from ones started earlier and transplanted.
Other good warm weather annuals to consider include any sunflower, tithonia, marigolds, morning glory and cosmos.
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