Lobelia are often used as a border plant in cottage gardens and can also be used in hanging baskets or in large pots to provide a display of potted colour, the plants create a lovely frothy and delicate contrast to larger flowers such as petunias and geraniums.
Very easy to grow, they simple wind their way through the gaps in plants, filling them in with ease. It will flower it's heart out as soon as the spring frosts are over and will continue to do so right up until the first ground frost of winter. This self-seeding variety flowers very quickly, often within a month or so of planting ands is an ideal cottage plant, as it will generally grow as a quasi-perennial, by renewing itself through naturalised seedlings.
A great little essential plant for all planting schemes.
Timing: Sow indoors in late winter to late spring.
Sowing to flowering is about 16 weeks; they will flower happily until the first signs of winter. To get the most from your plants, sow early in the year. However, Lobelia erinus have such a long flowering period, so long as temperatures are around 15 to 20°C (60 to 70°F) while they germinate they can be sown up to late spring.
Sowing:
Fill a seed tray or pot with moist seed compost. Stand the tray in water until completely moist and then drain off the excess water.
Sow seeds as thinly as possible over the surface of the compost. The finer you sow them, the easier pricking out will be. Mixing the seeds with silver sand may help a more even distribution of seeds. Lightly press the seeds into the compost. Do not cover them with soil as they need light to germinate. Place in warmth 15 to 20°C (60 to 70°F), and keep moist at all times.
Germination will take 10 to 14 days. Keep the seedlings in a light position, but shade from bright sun. When large enough to handle (usually after 5 to 6 weeks) transplant 5cm (2in) apart into trays of potting compost. It is easier to transplant little clumps of Lobelia seedlings than to try to transplant single seedlings.
Cultivation:
Gradually accustom plants to outside conditions for 2 to 3 weeks before planting out when danger of frost has passed, usually from the end of May. The plants will spread so allow 15cm (6in) between plants.
Lobelia erinus will grow best in a cool spot with partial shade. Before planting, add some organic matter or a controlled release fertiliser into the soil.
It does not like hot, dry weather; in midsummer they can be rejuvenated by cutting them back by half their height, which also will help them become bushier. Reapply fertilizer and water them well. Keep plants moist at all times, if the plant does dry out it will die back, if this happens cut it back and it should produce a second flush of growth.