What Are Geraniums From Seed?
Growing geraniums from seed offers a cost-effective and deeply satisfying way to cultivate a profusion of colour in your garden or patio containers. Instead of purchasing young plants, you start with tiny seeds, nurturing them through germination and growth until they develop into mature, flowering specimens. This method is particularly rewarding for gardeners looking to experiment with a wider array of cultivars, as many unique varieties become accessible when sourced as seeds.
- Starting from seed saves money compared to buying plants.
- Access to a wider variety of geranium cultivars.
- Provides a rewarding gardening experience.
- Requires patience and basic horticultural knowledge.
While commonly referred to as geraniums, the plants most often grown in UK gardens from seed are actually pelargoniums. True geraniums (hardy or perennial geraniums, also known as cranesbills) are typically propagated by division or cuttings, although some can be grown from seed. This article focuses on the commonly sown pelargonium types, which include zonal, ivy-leaved, and regal (Martha Washington) varieties, prized for their showy blooms and versatility in borders and hanging baskets.
Why Grow Geraniums From Seed?
The primary appeal of growing geraniums from seed lies in the sheer horticultural adventure and the potential for significant savings. A single packet can yield dozens of plants, drastically reducing the cost per plant compared to buying established specimens. Furthermore, seed catalogues often feature an extensive range of colours and forms not readily available as young plants in garden centres. This allows for truly bespoke planting schemes, enabling you to create unique combinations tailored to your specific aesthetic preferences. For instance, you might find unusual bi-colours or distinct petal shapes that add an extraordinary dimension to your floral displays.
Beyond the financial and aesthetic benefits, sowing seeds connects you intimately with the plant's life cycle. Witnessing the first tender shoots emerge from the soil is a profound experience that instils a sense of accomplishment and deepens your understanding of plant cultivation. It's an opportunity to observe the subtle stages of development, from delicate seedling to robust flowering plant, fostering a greater appreciation for the botanical world. This hands-on approach can also be an excellent educational tool for families, teaching valuable lessons about nature, patience, and the rewards of diligent care.
The Basics: Sowing Your Geranium Seeds
Embarking on your geranium-from-seed journey requires attention to detail, particularly regarding sowing time and conditions. The optimal period to sow pelargonium seeds indoors is typically from late winter to early spring, around 8-10 weeks before the last expected frost in your region. This timing is crucial as geraniums are sensitive to cold and will need a head start to establish before being transplanted outdoors when the risk of frost has completely passed and temperatures are consistently mild.
Preparing Your Seed Trays and Soil
Begin by selecting appropriate containers. Shallow seed trays or small pots are ideal, provided they have adequate drainage holes. Sterilising your trays and tools beforehand minimises the risk of fungal diseases like 'damping off', which can devastate young seedlings. A sterile, well-draining seed compost is essential. You can purchase a specific seed-starting mix or create your own by combining equal parts of peat-free compost and perlite or sharp sand. This ensures good aeration and prevents waterlogging, conditions that are detrimental to germinating seeds.
Gently fill your trays or pots with the compost, tapping them lightly to settle the soil without compacting it. Aim for a level surface, leaving about 1-2 cm space from the rim. Water the compost thoroughly and allow it to drain for a short while. This ensures the soil is moist but not saturated, creating the ideal environment for seed germination.
Sowing the Seeds
Geranium seeds are relatively large and can be sown individually. Place one or two seeds on the surface of the compost in each cell or pot. For larger seeds, you may need to cover them lightly with a thin layer of compost or vermiculite, roughly 3-5 mm deep. Some gardeners find success sowing seeds slightly deeper, around 0.5 cm, but it's vital not to bury them too deeply, as they need light and warmth to germinate. Ensure seeds are spaced adequately to avoid overcrowding later on.
After sowing, water the trays very gently. A fine mist spray is best to avoid dislodging the seeds. The key to successful germination for geraniums is consistent warmth and moisture. Place the trays in a warm propagator or on a warm windowsill, ideally maintaining a temperature of 20-25°C. Covering the trays with a clear plastic lid or cling film helps retain humidity, creating a microclimate conducive to germination. Check regularly for signs of germination, which can typically take anywhere from 7 to 21 days, depending on the specific variety and conditions.
Once seedlings emerge, ensure they receive ample light immediately. A bright windowsill is suitable, but if natural light is insufficient, consider using grow lights to prevent seedlings from becoming leggy and weak as they stretch towards the sun.
Nurturing Your Seedlings and Beyond
The period following germination is critical for the survival and healthy development of your geranium seedlings. As soon as you see the first signs of growth, it's important to adjust their environment. Remove any covers that retain high humidity to allow for better air circulation, which helps prevent fungal diseases. However, continue to keep the soil consistently moist, but never waterlogged. A fine-rose watering can or a gentle misting spray is recommended to avoid disturbing the delicate seedlings.
Providing the Right Conditions for Growth
Adequate light is paramount. Seedlings need at least 12-16 hours of bright light per day. If your indoor light levels are low, supplementing with artificial grow lights is highly advisable. Position grow lights a suitable distance above the seedlings, adjusting the height as they grow to maintain optimal illumination without scorching the leaves. The temperature should ideally be maintained at a slightly cooler but still warm level, around 18-20°C, once germination is established.
As the seedlings develop their first set of true leaves (which will look like miniature geranium leaves, unlike the initial cotyledons), it's time to think about transplanting them into individual pots. This process, known as 'pricking out', gives each plant more space for its roots to develop and reduces competition for nutrients. Use 7-9 cm pots filled with a good quality, peat-free potting compost. Handle the seedlings with extreme care, ideally by their leaves rather than the fragile stem, to avoid damage.
Hardening Off and Transplanting Outdoors
Before transplanting your young geraniums into their final outdoor positions, they must undergo a process called 'hardening off'. This acclimatises them gradually to outdoor conditions, such as stronger sunlight, fluctuating temperatures, and wind. Start by placing them in a sheltered spot outdoors for a few hours each day, gradually increasing the duration and exposure over a week to ten days. Protect them from harsh direct sun and strong winds initially.
Once hardened off and when all danger of frost has passed, typically from late spring onwards, your geraniums are ready for their permanent homes. Whether planting in garden beds, borders, or containers, ensure the site receives plenty of sunlight for the best flowering performance. Space them appropriately according to the mature size of the variety you are growing, usually 20-30 cm apart. Water them well after planting and continue to water regularly, especially during dry spells, to encourage strong growth and abundant blooms throughout the summer months.
The journey from a tiny seed to a vibrant, blooming geranium is one of the most rewarding experiences a gardener can undertake.
Alternative Approaches and Considerations
While starting geraniums from seed is a popular and accessible method, it’s worth noting that other propagation techniques exist, each with its own advantages. For gardeners seeking immediate impact or propagating specific, established varieties, taking cuttings from existing plants or purchasing young plants are common alternatives. However, for the beginner looking to fill a large border or numerous pots cost-effectively, seed sowing remains an excellent choice. It also allows for a degree of experimentation, as some seed-grown plants may exhibit unique characteristics compared to their parent stock.
Choosing Your Geranium Varieties
The world of geranium seeds is vast, offering a spectrum of colours, plant habits, and bloom types. For bedding displays, consider 'zonal' pelargoniums, known for their distinct leaf zones and upright growth. 'Ivy-leaved' pelargoniums, with their trailing habit and rounder leaves, are ideal for hanging baskets and window boxes. 'Regal' pelargoniums (Martha Washington), celebrated for their large, ruffled flowers, often require slightly more specific care and are best suited for containers where they can be protected from harsh weather.
When selecting seeds, look for reputable suppliers. Seed descriptions often indicate the expected height, spread, and flowering time, helping you choose varieties that best suit your garden's conditions and your aesthetic goals. Some modern F1 hybrid varieties are bred for uniformity and vigour, offering reliable results even for novice growers.
When to Plant Sunflower Seeds vs. Geraniums
For context, while geraniums are typically started indoors in late winter or early spring, other popular annuals like sunflowers have different planting requirements. Sunflower seeds, for example, are generally planted directly outdoors in late spring after the last frost when the soil has warmed up, as they grow rapidly and do not benefit as much from an extended indoor starting period. Understanding these distinct planting schedules is key to successful annual gardening. Similarly, while companion planting is a broad concept, focusing on compatible neighbours like marigolds or petunias for your geraniums, rather than entirely different plant types like sweet peas which have their own specific needs, ensures optimal growth for all.
If you have limited space or time, consider investing in 'pelleted' seeds. These are coated with a protective layer making them larger and easier to handle and sow accurately, reducing wastage and the need for thinning.