A picture of Geraniums, growing beautifully in a container
Geraniums are among the most beloved, widely recognized, and extensively grown flowering plants in the world, encompassing two distinct but commonly confused plant groups that share the same popular name. True hardy geraniums, belonging to the genus Geranium of the family Geraniaceae, are tough, reliable, and versatile perennials that thrive outdoors in temperate gardens year-round. The plants most commonly referred to as geraniums in everyday gardening conversation, however, are tender pelargoniums belonging to the genus Pelargonium, originally native to South Africa and grown as annuals or overwintered indoors in cooler climates.
The flowers of geraniums and pelargoniums are both undeniably beautiful but distinctly different in character and form. Hardy geranium flowers are typically open, flat, and five-petaled in shades of blue, purple, pink, magenta, and white, often with delicate veining on the petals that adds considerable visual interest and refinement. Pelargonium flowers are bolder and more showy, arranged in large, rounded clusters above the foliage in vivid shades of red, pink, salmon, orange, white, and bicolor combinations, with some varieties producing elaborate double flowers of extraordinary opulence and visual richness.
Hardy geraniums are indispensable perennials in temperate garden design, valued as much for their attractive, deeply lobed or cut foliage as for their flowers. They fill a remarkably wide range of garden situations with ease and reliability, from sunny, well-drained borders and rock gardens to shaded woodland edges and ground cover plantings beneath trees and shrubs. Many hardy geranium species and cultivars produce outstanding autumn foliage color, turning fiery shades of red, orange, and bronze as temperatures drop in autumn, extending their ornamental season well beyond their main flowering period.
Pelargoniums have been cherished garden and houseplants since their introduction to Europe from South Africa in the 17th century, quickly becoming indispensable fixtures of cottage windowsills, balcony boxes, and summer bedding schemes across the continent. They are divided into several distinct horticultural groups including zonal pelargoniums, ivy-leaved pelargoniums, regal pelargoniums, and scented-leaved pelargoniums, each with its own distinctive characteristics, uses, and ornamental qualities. The scented-leaved group is particularly fascinating, with varieties offering fragrances of rose, lemon, mint, nutmeg, and many other appealing aromas released when the leaves are touched or brushed.
Both geraniums and pelargoniums are remarkably easy, forgiving, and accommodating plants to grow, requiring relatively little specialist knowledge or equipment to cultivate successfully. Hardy geraniums thrive in most well-drained soils in sun or partial shade and require very little maintenance beyond an occasional trim after flowering. Pelargoniums are equally undemanding in their requirements, needing full sun, well-drained soil or compost, and protection from frost to perform at their best, rewarding minimal care with a continuous, prolific, and spectacularly colorful flowering display throughout the entire warm growing season.
Geraniums and pelargoniums have been valued beyond the ornamental garden for centuries, with several species having significant medicinal, culinary, and commercial applications. Scented-leaved pelargoniums — particularly Pelargonium graveolens — are commercially grown on a large scale for the extraction of geranium essential oil, widely used in perfumery, aromatherapy, and the cosmetics industry as a valuable and versatile fragrance ingredient. Hardy geranium species have been used in traditional herbal medicine across various cultures, and the edible flowers of both geraniums and pelargoniums are increasingly used as decorative garnishes in contemporary culinary presentations.
Gerenium Flower Seeds
How to Grow Geraniums From Seed
- Choose Between Hardy Geraniums and Pelargoniums — Before sowing, clarify which type of geranium you intend to grow from seed, as the two groups have quite different seed requirements and growing characteristics. Hardy geranium seeds often require cold stratification and patience, as they can be slow and irregular germinators. Pelargonium seeds, on the other hand, germinate relatively quickly and reliably under warm conditions, making them more straightforward to raise from seed and better suited to gardeners who are new to growing plants from seed.
- Source Fresh, Quality Seeds — Always purchase the freshest possible seeds from a reputable supplier, paying close attention to the seed packet date to ensure you are working with seeds from the current or most recent growing season. Pelargonium seeds in particular lose viability relatively quickly compared to many other flower seeds, and using fresh seeds significantly improves germination rates and the overall quality and uniformity of the resulting seedlings. Avoid purchasing seeds that are more than one or two seasons old whenever possible.
- Start Pelargonium Seeds Very Early — Pelargonium seeds need to be started very early indoors — typically twelve to sixteen weeks before the last expected frost date in your area — to allow sufficient time for the slow-growing seedlings to develop into flowering-sized plants by the time outdoor planting conditions are suitable. This extended indoor growing period is one of the most important factors in achieving a good display from pelargoniums grown from seed in their first season, as plants started too late rarely reach their full flowering potential before the growing season ends.
- Prepare Seed Trays With Fine Compost — Fill seed trays or small individual pots with a fine, well-draining seed-starting compost that has been thoroughly moistened before use. For pelargonium seeds, a compost with a relatively low nutrient content works best at the germination stage, as excessive nutrients can promote soft, weak seedling growth. Firm the compost surface gently to create a smooth, consistent sowing surface that will support even and uniform germination across the entire seed tray or pot.
- Sow Seeds at the Correct Depth — Pelargonium seeds have a distinctive, elongated shape with a feathery tail attached to one end, making them easy to handle individually and sow with reasonable precision. Sow each seed individually, pressing it gently into the surface of the moistened compost and covering it with a thin layer of fine vermiculite approximately one-eighth of an inch deep. Unlike some seeds that require light to germinate, pelargonium seeds germinate best with this very light covering that maintains darkness and consistent moisture around the seed.
- Provide Consistent Warmth for Germination — Pelargonium seeds require consistently warm temperatures to germinate successfully and reliably, ideally between 70–75°F (21–24°C) maintained consistently throughout the day and night. A heated propagator is the most effective and reliable way to provide and maintain these temperatures, particularly during the cooler early spring weeks when they are most commonly sown. Without adequate and consistent warmth, pelargonium seeds germinate slowly, unevenly, and with significantly reduced overall germination rates that can be frustrating for even experienced gardeners.
- Remove Seed Tails Before or After Sowing — The feathery tail attached to each pelargonium seed can sometimes cause seeds to clump together or stand upright rather than lying flat against the compost surface, potentially reducing the quality of seed-to-compost contact and affecting germination. Some gardeners prefer to gently remove the tail from each seed before sowing, while others sow seeds with the tail intact and simply press them firmly onto the compost surface. Either approach can work well — the important thing is ensuring good contact between seed and moist compost.
- Maintain Humidity During Germination — Cover seed trays or pots with a clear propagator lid or a sheet of clear plastic wrap after sowing to create a warm, humid environment around the seeds that reduces moisture loss and maintains the consistent moisture levels needed for reliable germination. Check regularly and remove excess condensation from the cover to prevent water dripping directly onto the seeds. Remove the cover gradually over several days once the majority of seedlings have emerged to acclimatize them slowly to lower ambient humidity levels.
- Provide Excellent Light After Germination — As soon as pelargonium seedlings emerge, move them immediately to the brightest available location or place them directly under grow lights for fourteen to sixteen hours per day. Pelargonium seedlings are particularly prone to becoming pale, weak, and excessively elongated if they do not receive abundant light from the very earliest stage of their development. Leggy seedlings produced through insufficient light rarely develop into compact, well-branched, floriferous plants regardless of the quality of care they subsequently receive.
- Water Carefully to Avoid Problems — Water newly germinated pelargonium seedlings with considerable care, as they are quite vulnerable to both overwatering and the damping off disease that often follows it. Always water from below by placing seed trays in a shallow dish of water and allowing moisture to be absorbed upward through the compost rather than watering from above, which keeps the compost surface drier and significantly reduces the risk of fungal damping off disease developing around the vulnerable base of young seedlings.
- Prick Out Seedlings at the Right Stage — When pelargonium seedlings have developed their first pair of true leaves and are large enough to handle safely without significant risk of damage, carefully prick them out individually into small pots filled with good quality multipurpose potting compost. Handle seedlings gently by their leaves rather than their fragile stems during this delicate operation, and water them thoroughly after potting to help them settle quickly and comfortably into their new individual containers without experiencing significant or prolonged transplant shock.
- Pot Up Progressively as Plants Grow — As pelargonium seedlings develop and their root systems expand to fill their initial small pots, pot them up progressively into increasingly larger containers to prevent them from becoming root-bound and to maintain the steady, continuous growth needed to produce well-developed flowering plants by planting-out time. Each time you pot up, use fresh, good quality multipurpose compost and water the plants in thoroughly after potting to help the roots establish quickly in the new, larger growing environment.
- Begin Feeding at the Right Time — Once pelargonium seedlings are well established in their individual pots and are growing actively and vigorously with visible new leaf production, begin feeding them every two weeks with a balanced, water-soluble liquid fertilizer diluted to half the recommended strength. As plants develop further and begin to show signs of flower bud development, switch to a fertilizer with a higher potassium content to promote strong stem development, vigorous root growth, and the abundant, long-lasting flower production that pelargoniums are so deservedly celebrated for.
- Harden Off Thoroughly Before Planting Outdoors — Before moving pelargonium seedlings outdoors permanently, harden them off very carefully and gradually over a minimum of two weeks, as these tender South African plants are particularly sensitive to the cold temperatures, direct sunlight, and wind that they will encounter in the outdoor garden environment. Begin by placing seedlings outside in a sheltered, warm, partially shaded spot for just a few hours each day, increasing their daily outdoor exposure progressively over the hardening off period until they are fully adjusted to outdoor conditions.
- Plant Out Only After All Frost Risk Has Passed — Pelargoniums are frost-tender plants that will be severely damaged or killed by even a light frost, so never plant them outdoors permanently until all risk of frost has completely and reliably passed and nighttime temperatures remain consistently above 50°F (10°C). Choose a sunny, sheltered planting position with well-drained soil or use good quality container compost for pot growing, space plants twelve to fifteen inches apart to allow adequate airflow, and water them in thoroughly after planting to help them establish quickly and begin their spectacular season-long flowering display without unnecessary delay or setback.