Over-Wintering Annuals

Sad to see the end of summer and therefore the end of  your favourite geraniums? Or lantana? Fuchsia, too? Why not keep them over till next year?

Pelargoniums (aka Geraniums) and Lantana are both super easy to over-winter

I adore pelargoniums (aka geraniums) and scented geraniums, too, so always keep a few of my favourites to over-winter in the greenhouse. Lantana is also becoming a new fave to keep from year to year, will be working on getting a collection of varieties.  

Many plants that we think of as annuals are actually pretty hardy, and also super easy to keep over. Try bringing in your prettiest coleus, lantanas, geraniums and fuchsias. 

There are several different methods you can choose from to over-winter yours ... I use them all ; )
  

1. Re-pot, clean up, and leave as they are. 

2. Cut back hard now and let flush out over the winter months. 

3. Take cuttings and throw away the 'mother' plants. 

Over-wintering plants in a winter greenhouse  

Regardless of which method you choose, keep these tips in mind.

They like to be kept cool and dry.
   

If you are going to keep them over inside the house, place on a bright window sill in a room that does not get overly warm, like in a basement or spare room, maybe? Ideally, start with a east or north facing window in fall and then move to a sunnier window in late winter, however this is not necessary for success.  

If you are over-wintering them in a heated greenhouse, set your thermostat at 5 - 7° C and open the door on occasion to let in some fresh air and prevent condensation.  

Condensation and high humidity bring on rot and fungal issues, so running a fan and opening doors/windows will keep the air moving and prevent moisture build up. See HERE for more information about winterizing your greenhouse. 

Water sparingly in winter, keep the soil moist but not wet. Do not mist or wet foliage! They want dry air but moist soil. 

 
So, here are the three methods....

1. Leave them as they are and keep them over

This method is the easiest of them all, if you have the space. I always use this one for lantana, and sometimes for geraniums if they are all abloom and not too leggy.    

- Remove spent blooms, plus yellow or brown leaves. 

- Wash entire plant with a strong jet of water to blow off bugs and eggs, then spray thoroughly all over with Safer's Insecticidal Soap. 

- After 15 minutes, rinse the soap off with yet another strong jet of water. This will not only remove the soapy film from the leaves, but also cleans off any dead bugs, eggs, or remaining pests.       

- Re-pot into fresh, clean potting mix with a bit of manure added for nutrients. Do not give additional feed until February. Lantana prefers to be slightly pot bound, so I usually leave it till late winter. Feed  with a weak liquid seaweed solution every week or two, as you water.   

- Continue to remove spent blossoms and yellowing foliage throughout the winter, and check for bugs. 

2. Cut back and clean up  (Semi-dormant) 

I use this method the most. Use when over-wintering lanky, big or bushy geraniums (ivy, zonal or scented), and always on fuchsias.    

- Remove all blossoms, old, big leaves, and cut back long, lanky stems. This will promote nice and bushy plants next year. With really over-grown plants like scented geraniums, trim the stems down to just a few inches high, does not matter if there are any leaves left on the plant at this time.   

- Clean them up with the water and soap spray, as above, to prevent bugs from invading your greenhouse or home. 

- I always pot them up into a nice, clean pot with fresh potting soil and a bit of manure at this time, however, you can leave them till spring, if you prefer. In that case, feed with a wee bit of liquid seaweed each time you water to keep them going till you re-pot.   

Cut back big, bushy scented geraniums like this 'Prince of Orange' 

before bringing into the greenhouse.  

Take down to just a few inches high and it will grow back big and bushy again next year. 

Take cuttings now 

3. Taking cuttings. 

The third method is to take cuttings and toss out the mother plant. With this one you get lots of fresh, new plants for next year. I use this method mostly for scented geraniums, and herbs like rosemary, and lavender.  

- Take several 3 to 4 inch long cuttings from new growth. Make sure that they are soft and pliable as hard and woody stems will not 'take' easily.    

- Pick out a wide, shallow pot, 4 inches deep, ideally not terracotta as it dries out so fast. Fill with gritty, well draining potting mix.  

- Swish cuttings in soapy water to remove any bugs. 

- Trim off all foliage along the stem except the topmost two or three leaves. Dip cutting into rooting powder and then insert deep into the pot. Push them down as far as you can, so that the bottom leaf is just above soil level. Pop in as many cuttings as you want per pot, as long as they are not touching each other. 

- Water, keep soil moist, not wet. 

- After a month or so, you can gently tug on the cutting to check for rooting. Be careful to not pull the cutting right out. If you meet with no resistance, leave in for a few more weeks. Slight resistance means it is not quite ready, but is well on it's way. Resistance means that it has a good root system and ready for it's own pot. Do not just yank it out or you will tear the new roots, use a small spoon or pencil to loosen the soil around the new roots, and gently lift out. Pop into it's own pot.      

What to do in late winter? 

In early spring, they will start to put on lots of new buds and blooms

- Start feeding once a week in February. I generally start with a higher nitrogen feed at first, like the 'Alfalfa Tea' that I make for my seedlings. However, liquid seaweed works great, too, especially as a foliar feed.   

- Switching to a higher phosphorous feed in spring and summer will promote more blooming.  

Happy gardening!