Bulbs Planting Guide - Summer
Begonias
Plant 3cm deep, 15cm apart in well-drained soil in dappled shade. Keep any leaf growth above soil level. Ensure adequate moisture, but do not over water. Use slow-release fertiliser and spray with fungicide for powdery mildew if required. Deadhead regularly. Tubers can be lifted when plants start to die down. Begonias do not multiply but get bigger every year.
Dahlias
Plant 5-6cm deep, 50cm apart in well-drained soil in full sun. Fertilise well with blood and bone and again with liquid fertiliser when flowering and spray with fungicide for powdery mildew if required. Larger varieties may need staking. Deadhead regularly. Dahlias do not need to be lifted every year, but can be lifted June/July and stored in a cool, dry, frost free place in sawdust to prevent shrivelling up.
Gladioli
Plant 8-10cm deep and 15cm apart in a sheltered position with full sun and good drainage. Gladioli will flower approximately 100 days after planting so can be stagger-planted for a continuous display. Plant in groups for best effect. Water adequately and use minimal fertiliser (avoid animal manure). Spray for thrips if required . Tall varieties may need staking. Lift corms in autumn to avoid rot. Do not wait for leaves to die back. Dry corms in hot water cupboard and then store in a cool dry place for next year. Dust with insecticide to prevent infestation.
Calla Lillies
Plant straight away. It is important not to plant the bulbs until the soil temperatures reach around 14 degrees. In very cold areas they perform best if planted in pots rather than the cold ground. Plant bulbs with shoots facing upward and the smooth surface on the bottom. These Callas make excellent patio/conservatory plants in all areas. Plant 7-10cm deep, 12 cm apart in free draining soil in semi-shade to full sun. Apply a general garden fertiliser low in nitrogen. FOR BEST RESULTS, lift tubers on die-down and store in a cool, dry area for replanting next season.
These bulbs should flower well this summer but a sudden cold snap during active growth can sometimes shut down their ability to flower. If this happens be assured that they will definitely flower prolifically in the second season.
Callas in Pots
Callas can be grown in pots given the following conditions:
- bulbs should be in big pots, i.e. 20 cm diameter– they do not like their pot/root zone to get very hot
- best kept in semi-shade
- keep pots at a uniform moisture level - don't allow to completely dry out.
Amaryllis (Hippeastrums)
Handle bulbs carefully to avoid damage. Plant the bulb in a pot in good quality potting mixture that contains a six-month slow release fertiliser in a pot at least 150 mm wide. Plant the bulb with the top third above the mixture and make sure the roots are well spread out. While the bulb is growing, use tepid water sparingly to keep the mixture just moist, but not wet. Do not water over the nose of the bulb. Do not allow water to sit in the tray underneath the pot. If you have used a good mixture with slow release fertiliser then no additional fertilising is required. Amaryllis like a constant temperature of around 20 degrees C. Keep the pot in a warm room, in full light or outside in a sheltered area.
Flowering usually will begin three to five weeks after planting. Once the bulb is flowering remove the pot from direct sun to extend the life of the flower. CARE AFTER FLOWERING: When the flower is spent, remove the flower stem as close as possible to its base. Some liquid fertiliser can be given in the water now, as the bulb needs to be well fed for the next few months to be able to flower well next season. Keep watering the bulb for the next two to three months as the thick green leaves make it an attractive plant to have in the house even after flowering.
Secrets for successful re-flowering
Flowering is initiated by a stress period of cool or dry conditions. The stress period must be at least 10 weeks to be effective. These conditions can be provided by keeping the bulbs dry during winter. Re-pot the bulb into fresh mixture from early to late Spring and follow the above growing instructions. Alternatively place the potted bulb outdoors for the winter months in a protected position. It will lose most of its leaves but this is not a problem. Simply re-pot the bulb and bring it indoors in Spring.
