From our perspective as plants, successful transplantation into the outdoor world is a critical and vulnerable moment in our life cycle. The timing of this event is not a mere suggestion; it is dictated by our fundamental biological needs for soil warmth, stable air temperature, and specific light conditions. Getting us into the ground at the right time ensures we can establish our root systems efficiently and dedicate our energy to producing the vibrant blooms you so enjoy. Here is a regional guide based on the environmental cues we require.
Our most non-negotiable requirement is absolute freedom from frost. We are tender annuals, meaning our succulent stems and leaves are composed mostly of water. When frozen, our cell walls rupture, causing irreversible damage that leads to collapse and death. Therefore, the single most important date to know is your local average last spring frost date. We implore you to wait until after this date has safely passed and to monitor short-term forecasts vigilantly for unexpected cold snaps. A sudden late frost is a death sentence for us.
Our needs are universal, but the calendar varies greatly depending on your location's climate.
In these warmer zones (USDA Zones 8-10), conditions often become suitable for us earlier. You can typically plant us outdoors from early March to mid-April. The soil has warmed sufficiently, and the threat of a hard freeze has largely passed. However, be cautious of an unusually late cold spell, which can still occur. The consistently warm nights in this region are ideal for our root development.
For these areas (USDA Zones 5-7), patience is key. The optimal window for planting us is generally from mid-May to early June. The soil in early spring is often too cold and wet, which can cause our roots to rot rather than grow. Waiting until late spring ensures the soil is warm and workable, allowing us to establish quickly and begin flowering without the stress of a chilly root zone.
In these cooler climates (USDA Zones 3-5), the growing season is shorter, and the wait is longer. The safest time to introduce us to your garden is from late May through early June. Rushing to plant us on a warm day in early May is a tremendous risk. A single night of frost will undo all your work. It is far better to wait for stable, consistently mild temperatures, both day and night.
Your climate is often mild but presents a different challenge: cool, damp soil. While your last frost date may be relatively early (April), the soil may take longer to warm up. Aim for a planting time from late April to mid-May. Ensure we are placed in a location with protection from strong winds and, crucially, in well-draining soil to prevent root rot from excessive moisture.
Your primary challenge is intense sun and heat. For us, impatiens, the scorching afternoon sun is detrimental. We thrive in filtered shade. The best time to plant us is in early spring (February-March) to establish before the extreme heat arrives, or in late summer/early fall for a second blooming season. Avoid planting us during the peak summer heat, as the stress will cause us to wilt, stall growth, and require constant watering to survive.
