You can do this the hard way, or buy a readymade hanging basket from your local purveyor of high altitude horticulture. If the latter, you should get a perfectly reasonable collection of several annuals and if you are fortunate, the container will not be made of hessian or woven reeds and thus be designed for the bottom to fall out at a moment of maximum inconvenience. If you are still reading this, I am assuming that you are of my bent. I like the cut of your jib. Let’s make something extravagant.
This year’s hanging basket
First line the biggest basket that you can acquire with coir, then a layer of plastic cut from compost bags, black side outermost. Make the circles too big, as trimming off the excess is easier than sticking it back on. Lift the structure by the chain and hold it as it will attach to the sturdy and meticulously fixed wall hook. Mark the side that swings to the front with string, since this will be where your favourite plants should be sited. Failure to include this step will result in the display rotating once installed, to show a shagged Nepeta and possibly a spreedy Begonia as your centrepiece. No amount of farting about up a ladder will bring your best specimens into prominence unless you plan it that way.
Osteospermum “Violet Ice” (Cape daisy)
Thoroughly water the plants that you have chosen an hour before you evict them from their pots. Mix fresh compost, slow release fertiliser and water retaining gel. The latter will have to be broken from an unsavoury blob that has festered in the shed all winter, grabbing moisture to form a claggy mess that you hesitate to handle. Choke down your revulsion and get on with it. Cut planting holes through the liners in a cross shape before adding any soil. Rest the lined basket on a bucket. Push stems and leaves through the slits, supporting the roots on the inside with handfuls of compost. One tier of trailers may be sufficient in the sides, the remainder being placed around the top. Put a couple of upright growers in the centre, to give it some height. Make sure that each plant has plenty of soil around it, without being stingy with the greenery. I prefer a colour theme to these presentations; this year I’m going for white, enlivened with a little lilac. I’m aiming for elegance but since I’m a tart at heart, I’ll be happy with pretty.
Rosa “Margaret Merril”
Hang it up, then water it until the excess drips out. If you do this the wrong way around it will be extremely heavy. You cannot sue me for the cost of hernia trusses, back braces, dry cleaning bills for dampened trousers howsoever caused and concomitant loss of pride, because I warned you. Ply the hose or can again after a few hours, to make sure that the earth is washed into contact with the roots and to get yourself into the habit of daily irrigation. Later in the season, you may add tomato fertiliser, Miracle Grow or similar, to give the show a boost. One of my customers used to splash Guinness into her hanging baskets, whilst never offering me liquid refreshment of any kind. This is the only time that I have been envious of a lobelia.