Here's a quick reference guide to growing Scented Leaf Pelargonium - Scented Geraniums in the UK and Ireland. 
We have used a bulletted format so that you don't have to read mountains of facts.  The information applies to all the other groups of pelargonium as well and we hope you find it helpful. 
See also Hot Topics where we post regular articles.
Source of Information: 
Leaflet supplied by H. V. Ralph, 1992, Pelargonium and Geranium Society.  Website:
Our own personal experience of growing and the numerous books we possess on the subject of Pelargonium that we constantly refer to.
Tip:  Good books about Scented Leaf Pelargonium are scarce and mainly you will come across the odd chapter on the scented leaf group in a general pelargonium book.
Henry J Woods is our recommendation – available second hand on Amazon for a few pounds.
  • It's very important to keep the plants warm - minimum of 5C or 40F
  • Heating for the cold months -
      • glasshouse, polytunnel - ideally a thermostatically controlled heater, i.e. Bio-Green Indiana which has numerous settings and takes in hot air from the top of the environment and recycles.  We recommend this type of electric heater and it is very affordable to run.
      • garage, outside shed - it's handy to have a spare convector heater for extremely low night temperatures
      • inside the home - not everyone heats every single room in the house and it is important to remember that you might still lose plants to very low night temperatures and frost, even inside.  Remedy is to move plants away from cold windows and/or move to a warmer room.  Do not site over radiators.
  • Horticultural fleece - is not expensive and will protect plants from a certain amount of frost in glasshouses, tunnels, sheds, garages and inside the home.  It's always worth having some.
  • Keep plants clean by frequent inspections and remove all decaying debris
  • Always look underneath the lower leaves and in the centre of the plant as this is where there's a greater tendency for leaves to decay
  • Watering - plants should be kept relatively dry and provide water only when absolutely necessary.  Indoors, you should monitor the plant and if it is continuing to grow you would provide water.  Watering from below is always more effective and is the recommended method.
  • Feeding - there is a difference of opinion on should you or shouldn't you?  I have read books where it is advised that you continue feeding all year long by providing a half strength feed over the winter months, whereas others say don't feed.  I do not feed during December and January and the plants do not suffer.  It's a matter of preference.  Indoors, you need to monitor whether the plant is continuing to grow and if it is you would feed.
  • Ventilation is required and if growing in a glasshouse or polytunnel open at least one door or window on milder days.  I have opened the doors on all but the very coldest and dampest of days throughout December and January.  As a guide if the outside temperature is above 2C provide ventilation.  Timewise, from 10am to 3pm when the temperature suddenly drops.
  • The light levels are low during this month, resulting in a continued state of dormancy from December.  However, there are exceptions and I do find that some of the Scented Leaf group continue to grow and flower whilst others really do slow down.
  • You may spray with a fungicide to prevent and check disease, although with continuous inspection and overall good housekeeping I don't feel that this is completely necessary.
  • Have you swept the glasshouse or tunnel floor recently?  Jeyes Fluid is an effective discinfectant for floors, work tops, benches, walls and glass.  I use it everywhere.
  • The light levels are improving as the days begin to lengthen and the plants begin to 'wake up'
  • Begin to increase the water and provide a good balanced feed to assist new growth.  Feed approx. every 1 - 2 weeks.
  • If you didn't check the root system last autumn do it now.  A compacted root system in a too small pot will inhibit healthy growth.
  • Repot your plants if they need it into a good quality and free draining compost.  Choose a pot that is slightly larger than the root system.
  • If you don't have a lot of time it is a good idea to include a slow release granular feed when you repot your plants, ideally a 6 or 9 months one.
  • By the end of this month you can start taking new cuttings - see our Hot Topics for the different methods.  Bottom heat will assist rooting but the main thing is that they receive plenty of light, are not in a draughty or damp position.  Do not put in a propagator as pelargonium cuttings do not like being covered.  It is not necessary to use a rooting hormone although opinion is divided on this.  Always label every single cutting as this is one of the ways that the names of SLP's get mixed up!!
  • Pot on your cuttings that were taken last autumn and begin to feed at this time.
  • If you send off for new plants each year this is the month that you should be placing your order.  If you do not have space inside to grow your plants on you may place your order on our website and specify that you would like a later delivery date, i.e. late April or May.
  • Spring is almost here and is a busy time for all gardeners, especially the pelargonium grower
  • When you receive the plants that you have ordered from Catalogues and the Internet it is important that you pot them up as soon as possible.  Do not delay!
  • Continue to water and feed with a balanced liquid fertiliser
  • Epson Salts or Magnesium - SLP's love this!  Spray the leaves to improve the leaf colour, will make them much greener.
  • The light and temperature are improving and SLP's need both to put on plenty of new growth
  • Ventilation is required whenever possible
  • Beware of the March frosts!!  Frosts are still a real danger in the UK & Ireland right through to the end of May.
  • Continue to inspect the well being of your plants and remove any decaying plant matter
  • Inspect the top and underside of leaves for pests and take action early before they become a real problem.  We recommend bio-control and possibly Encarsia on cards.  We'll post an article in our Hot Topics later in the year and report back as to whether Encarsia has been effective.  After considerable research we are getting mixed information as to the suitability of Encarsia with Scented Leaf Pelargoniums.  For a non-bio prevention use a systemic insecticide.
  • Pests - SLP's are prone to whitefly in particular and it is near enough impossible to totally eradicate these.  Be vigilant as whitefly will cause a lot of damage.  I find that they tend to get a grip when watering is erratic or when the compost becomes too dry.  Look out also for greenfly crawling around the compost and along the stems of the plants.
  • Continue your cuttings programme
  • Spring has arrived and all plants are putting on rapid growth
  • Daylight hours are now much longer and the warmer days are beginning
  • Ventilation daily is now becoming imperative as the glasshouse and tunnel temperatures are much higher inside than it is outside
  • In a good sunny year it might be necessary to provide shading
  • Pinch out the tips of the plants to encourage bushy growth and to shape them.  Rotate the plants on a regular basis to ensure growth is even.
  • Use the pinched out tips as new cuttings
  • Provide more space between the plants as this allows air to circulate more freely and helps them grow in a more even manner
  • Continue to monitor your plants, provide regular watering and feeding
  • As your plants grow pot them on into larger pots
  • Large containers and hanging baskets for the summer - plant up now in order that your plants are well established and ready to put outside late May/early June
  • If you grow the larger flowering types of pelargoniums, give a high potash feed which encourages the production of good blooms later, especially Regals.
  • On a warm day give the glasshouse or tunnel floor a good hose down and a sweep.  Remove anything that shouldn't be in there!!
  • During the day time you may begin to harden off your plants, take them outside for a few hours each day and gradually increase the time.  Don't forget to bring the plants back in as there is still a risk of night frosts
  • End of the month, weather permitting, the plants may be safely kept outside for the summer months - plant in borders or in containers
  • Shading for the glasshouse and tunnel - if you haven't already done this it should be done by late May as the light is much stronger and brighter and the temperatueres are now rapidly rising
  • Early cuttings should now be ready to pot on
  • Monitor your bio-control and introduce at regular intervals, or continue to spray with a systemic insecticide - pests breed at a rapid rate from late May and should be dealt with quickly
  • Feed plants weekly on a full strength dilution and occasionally spray the leaves with epson salts to improve leaf colour
  • Water - over the coming months as temperatures rise do not let your plant pots dry out, water on a regular basis or consider putting in a drip feeder system.  Capillerary matting is another good option.
  • Ventialtion - vent at every opportunity
June and July
  • Your plants should now be looking really good and coming into peak condition
  • Tidy your plants up on a regular basis and remove dead and decaying plant material as soon as possible - it helps cut down the pests
  • Damp down the floors in the glasshouse or tunnel on really hot days, it creates humidity and lowers temperatures
  • Continue to feed, water, ventilate and take action against the pests, i.e. whitefly and greenfly etc.
  • Pot up more of the cuttings that you have been taking over the past couple of months
  • Further cuttings may still be taken, use some from the mature plants below
  • Mature plants - at the end of this month cut them back quite hard.  Treat any open wounds with a powder fungicide to prevent disease and dieback.
  • As flower heads die you might want to have a go at collecting some seed.  Please note that in SLP's plants that are grown from seed will rarely come true to type but it's good fun as you don't know what you'll end up with.
  • Continue to water, feed, ventilate etc. as previous months
  • Continue with a programme of cutting back any plants that you intend to keep for next year
  • Outside plants should be dug up during this month, cut back, roots trimmed and dusted with a fungicide powder prior to being brought back into the glasshouse or tunnel, or shed/garage.
  • Container grown plants should also be cut back, checked for pests prior to being brought back inside.
  • Young plants that were taken from cuttings should now be stopped by pinching out the growing tip
  • The annual glasshouse/tunnel/shed maintenance job - before bringing all of your plants back inside this is a good month for doing the routine jobs such as:
    • remove shading
    • wash and disinfect thoroughly - anything and everything in sight
    • replace damaged glass
    • repair tears in tunnel plastic
    • treat timber with a wood preservative
    • insulate the inside of glasshouses/tunnels and sheds - we use a large bubble which is bought on a big roll.  It saves heaps of money over the winter in heating costs.  It's also a good idea to do this if you don't have heating, electric etc.
  • Indoors - bring in your plants during this month and place as near to a sunny window as possible.  Good light levels are essential and this should be kept in mind.
  • Indoors - pinch out the growing tip and stop your plants. 
  • Indoors - turn the plant pot on a regular basis to ensure all parts receive enough light.
  • If you didn't manage to get everything done by late September you have possibly a couple of more weeks to get everything finished prior to the winter setting in.  Don't delay any longer.
  • Minimum/Maximum thermometers - it's a good idea to have these wherever you are storing your plants, as it cuts out the guess work.
  • Temperature should be no less than 5 - 6C/40-42F, which will keep your plants alive until the Spring
  • Water and feeding should now be reduced accordingly to the weather conditions, although if we should be lucky enough to enjoy an 'Indian Summer' these would be maintined at their previous levels
  • Mildew and Botrytis - keep your plants well spaced and ventilate as much as possible.  Avoid a damp atmosphere.
  • Continue to pot up cuttings.  Stop young new plants.  Pot on the larger plants.
  • It is still possible to take some good cuttings during October but if you've followed a cutting programme throughout the summer months you should have enough by now.
  • All of your plants should now be safely housed indoors, whether this be in a tunnel, glasshouse, the shed, garage or the home
  • Leaving your SLP's outside all year round.  This is not a good idea!!  I am amazed how many people take this risk and we then receive emails in the Spring to say that they have lost their cherished plants.  A little effort goes a long way - take our advice and don't take the risk of leaving your plants outside, even if you do live in a coastal region, or anywhere for that matter.  SLP's are classified as a Half Hardy Shrub, which means that in the UK and Ireland they do need inside winter protection.  They are definitely NOT frost hardy.
  • This month is similar to January and it's a good idea to continually monitor your plants for leaf debris and decaying matter - remove this as soon as possible.
  • A damp month - choose a fine day to use a fungicidal spray or dust against botrytis.
  • Water - minimum amount required
  • Feed - at your discretion
  • Water - if in doubt, don't!!
  • The quietest gardening month of the year for the pelargonium grower!!
  • Time to browse our website and make your wish list for the Spring
  • A month when we long for Christmas to be over and we can start our growing all over again!!
The Calendar is intended as a quick reference guide
If you have any questions or are unsure of what to do with your Scented Leaf Pelargoniums
you may email us here
Contact Us
Happy Gardening
Annie & Guy

Powered by Create Ecommerce