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Xela's Garden

Pelargonium - zonal [V]

Genus: Pelargonium.

Species: Pelargonium hortorum.

Seeds sown 01.11 Vistabile

Zonal: These are mainly derived from P. inquinans and P. zonale. Upright, bushy, succulent-stemmed perennials grown for their single or double flowers. Some have attractive foliage. This type is most commonly used for bedding displays

Cultivation:
Pelargoniums can be grown in borders or containers. In borders or beds, plant in fertile, neutral to alkaline soil. Most prefer full sun. Regal cultivars prefer partial shade and zonal cultivars will tolerate some shade.
For indoor or outdoor container cultivation use well drained soil-less multipurpose compost or soil-based compost such as John Innes No 2.
If growing indoors or under glass grow in full light shaded from scorching midday sun.

Watering and feeding:
Water moderately during the growing season from spring to summer, avoid the compost becoming too wet and provide good ventilation. Apply a balanced liquid fertiliser according to the application instructions on the packet, every 10-14 days in spring. Once flowers start to form, switch to a high potassium fertiliser such as tomato feed. Water only sparingly in winter. Many will continue flowering if kept at 7-10°C (45-50°F).

Overwintering:
Pelargoniums are usually grown as annuals, but with a little care, they can be carried through the winter using one of the methods described below:
Method 1:
Overwintering by taking cuttings:-
This method is useful where there are large numbers of plants to overwinter; it suits soft-stemmed pelargoniums that cannot be kept in a semi-dormant state as per method 3.
Take softwood cuttings in late summer and discard the old woody plants
Once the cuttings have rooted, they can be overwintered in trays of compost kept on a well-lit indoor windowsill
Water the tray only sparingly in winter, allowing the compost to dry out between watering
Start feeding in late winter, giving a balanced liquid fertiliser every seven to 10 days according to the application instructions on the packet
Pinch out the shoot tips in late winter to encourage bushy growth
Pot up individually in mid-spring
Harden off and place outside once the risk of frost has passed

Method 2:
Overwintering in containers under glass:-
This method is useful where there are only small numbers of plants to overwinter and space in the glasshouse or conservatory to keep them.
Lift and pot those growing in the soil before the first autumn frosts. Cut them back to 10cm (4in) at this time. Use John Innes No 1 potting compost
Keep the plants in their pots over winter, in a light, frost-free position
Very little water is needed until growth resumes in spring
Re-pot into John Innes No 2 potting compost in mid-spring
Harden off and place outside once the risk of frost has passed

Method 3:
Overwintering in a semi-dormant state:-
This method is only suitable for varieties with tough woody stems, but is useful where there are large numbers of plants to overwinter.
Lift plants from the ground or pot and shake off excess soil or compost from the roots
Allow the foliage and stems to dry off in a frost-free place and then wrap the plants in newspaper or hang them upside down from the shed roof (which must be frost-free)
Plants which survive and show signs of growth in early spring should have their roots soaked in water for a few hours before being potted up cut back to about 10cm (4in)

Pruning and training:
Many pelargoniums are naturally bushy. They can be pinched back in spring or early summer to encourage further branching. Tall, vigorously growing cultivars can be trained on canes to form a pillar. Young plants of trailing ivy-leaved cultivars are best pruned back to promote branching.
Deadhead plants regularly to promote flowering.
If kept actively growing all year round, the majority of pelargoniums can be renovated by hard pruning in spring.
Those that are overwintered in a semi-dormant state (method 3) have already been cut back in autumn and should not need further pruning.
Propagation:
Zonal F1 and F2 (bedding type) pelargoniums and species pelargoniums can be propagated by seed. Sow in late winter and grow on in a protected environment such as a heated greenhouse.
Pelargoniums can also be propagated by taking softwood cuttings from spring to autumn.

Problems:
Pelargoniums are easy to grow, but there are a few things worth watching out for:
Pelargoniums can suffer from viruses transmitted by sap sucking insects such as thrips, or by cross-handling of plants and tools, like knives or secateurs
Roots of container grown plants are prone to vine weevil larvae damage
Poor air circulation and damp conditions favour diseases such as grey mould and rust
They can also suffer from leafhopper, root mealybug and whitefly
Dense clusters of distorted leafy shoots, often close to ground level, are leafy gall
[Source: http://apps.rhs.org.uk/advicesearch/profile.aspx?pid=338 ]

Photos of this plant

Reminders for this plant

Due about 11 years ago:

Sow indoors

Sow in late winter

Prune

pinch back in spring or early summer to encourage further branching.

Repot

Re-pot overwintered plants into John Innes No 2 potting compost in mid-spring
Harden off and place outside once the risk of frost has passed

Due over 10 years ago:

Lift

Lift and pot those growing in the soil before the first autumn frosts. See plant notes

Due about 10 years ago:

Take cuttings

take softwood cuttings from spring to autumn.