Petals come to each other but do not overlap in valvate/imbricate aestivation.

Explanation

**Step-by-Step Solution:**

1. **Understanding Estivation**:
- Estivation refers to the arrangement of petals (corolla) and sepals (calyx) in a flower. It describes how these floral parts are positioned relative to one another when the flower is in bud form.

**Hint**: Remember that estivation is all about the arrangement of flower parts before they bloom.

2. **Types of Estivation**:
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