Pelargoniums, often called Geraniums, can either be tender annual plants which die off at the first frost, or more hardy and survive for many years. Mine have lived outside in a window box for some twenty years with little maintenance.
Last year they appeared so lacklustre and straggly I believed they were due replacement. However they deserved a last chance so this spring I made two changes which transformed them.
Soil: The top couple of inches was dug out and fresh potting compost, bought bagged from a garden centre, was added.
Fertiliser: These are concentrated sources of plant nutrients. There are a number of expensive products on the market with exotic names and colourful packaging. However it’s the NPK Fertiliser label which is important because it’s a uniform guide which has to comply with EU and UK regulations.
On one make of summer citrus feed it’s 25:15:15
This means it’s 25% nitrogen, 15% phosphorus and 15% potassium.
(N) Nitrogen is important for strong growth and lush green leaves.
(P) Phosphorus is needed for healthy roots and stems.
(K) Potassium helps the plant produce flowers in abundance.
Garden centres and larger supermarkets carry ranges of reasonably priced fertilisers and supplements.
An old favourite, Murphy’s Sequestrene Plant Tonic comes in sachets and mixed with water rejuvenates tired old plant and improves their colour. It provides iron in chelated form which allows acid loving plants to absorb nutrients through their leaves and roots even in alkaline soil. It only needs to be applied once a year and it will make all the difference.
There are different schools of thought to the best way of applying fertiliser. Some are cautious of ready mixed liquid varieties preferring to mix up their own. Others recommend sprinkling the powder on top of the soil and watering in. It’s really important to read the instructions on the packet and carefully follow them.
Pelargoniums are easy to propagate. Cut through the stem with a sharp knife, dip in a pot of rooting powder then push into freshly watered soil. That’s it. Misting Pelargoniums with a hand held spray containing warm water and fertiliser really helps, especially if we have a dry patch.
Pelargoniums also benefit from ‘dead heading’, which means breaking off the head of the stems as soon as they have flowered. Always search for dead leaves and remove any found. The plant really appreciates the attention.