Moss Rose Seeds - Portulaca grandiflora

2, 3, 4, 5, 6, 7, 8, 9, 10, 11

USDA Zones 2-11 - Grows as a warm-season annual across all zones. It is a tender perennial in zones 9-11 but is most often grown as an annual due to its heat-loving nature.

Best performance across all zones where it receives full sun and has a long, hot growing season. Moss Rose is a sun-worshipper and its flowers will open in response to bright sunlight.

Northern Zones (2-7) - Plant after the last frost date when the soil has warmed. For an earlier start, sow seeds indoors 4-6 weeks before the last expected frost and transplant after all danger of frost is gone.

Hot Climate Zones (8-11) - Can be planted in early spring for summer color. In the hottest desert regions, planting may be done in late summer for fall blooming.

Soil Temperature - Requires warm soil for germination. A minimum soil temperature of 65F is needed, with an optimal range between 70F and 85F for quick sprouting and strong seedling growth.

Growing Season - Requires a minimum of 60 frost-free days to mature and bloom, making it a reliable annual for almost all climates.

Learn more about USDA Hardiness Zones here

When to Plant:

Indoors: Start seeds 4-6 weeks before your last expected frost date.

Outdoors: Direct sow seeds after all danger of frost has passed and the soil has consistently reached at least 65F. Moss Rose thrives in warmth, and cold soil will prevent germination.

Seed Starting:

Prepare a Seed Tray: Fill a seed tray or small pots with a well-draining seed starting mix.

Sow Seeds: The seeds are very small. Mix them with a bit of sand for easier spreading, then scatter them on the surface of the soil. Do not cover the seeds with soil, as they require light to germinate.

Water: Gently mist the soil to moisten it. Do not use a heavy stream of water, which can wash the tiny seeds away.

Provide Warmth & Light: Place the tray in a location with direct sunlight or under grow lights, ensuring a consistent temperature between 70F and 85F. A heat mat is ideal for maintaining the necessary warmth.

Germination: Seedlings should emerge in 10-14 days. Continue to keep the soil moist but not waterlogged.

Thinning: Once seedlings have their second set of true leaves, thin them to be 6-12 inches apart to allow for proper air circulation and growth.

Transplanting & Direct Sowing:

Hardening Off: If you started your seeds indoors, gradually expose the seedlings to outdoor conditions over a period of 7-10 days before transplanting.

Choose a Location: Select a spot in your garden that receives full sun (at least 6-8 hours a day). Moss Rose needs full sun to open its flowers.

Soil Prep: It is not picky about soil type, but it must be well-draining. It will thrive even in sandy or gravelly soil.

Planting: For transplants, plant them at the same depth they were in their pots. If direct sowing, scatter the seeds thinly.

Watering: Water newly planted seedlings lightly until they are established. Once mature, Moss Rose is extremely drought-tolerant. Only water during extended dry spells, allowing the soil to dry out completely between waterings.