You may have noticed gaps appearing in borders or simply want to have more of a particular plant type in your garden, but the expense of summer holidays may be eating into your gardening budget.
Yet you can increase your plant stock for very little money if you find self-sown seedlings springing up in your garden over summer or look to existing healthy plants to increase your stock.
Here are five ways to increase your plant stock for free.
1. Find self-sown seedlings
Take a look around your garden to look for self-sown seedlings. They may have popped up in borders or even just be emerging in gravel paths or other unlikely spots. In August you’ll often find quite large patches of plants such as hellebores, which are worth potting up.
It may be difficult to tell the difference between the seedlings you want to keep and the weeds you don’t, but look at nearby plants to identify leaf forms, then once the seedlings have their first true leaves you should be able to tell them apart.
Dig up the seedlings and pot them up, labelling your pots as you go. They’re best off in a shady cold frame or shady windowsill indoors while they establish, and you should be able to plant them out in the garden by next summer.
2. Take semi-ripe cuttings
Many plants are suitable for this technique in August and early autumn, including roses and lavender, sage, buddleia, hebe, nemesia and dianthus, as well as ground-cover plants and other deciduous and evergreen shrubs.
Semi-ripe cuttings are taken from new shoots from the current season’s growth which have turned slightly woody at the base. Choose shoots which are young, vigorous and firm to the touch, ideally which are non-flowering.
Trim them to around 10-15cm (4-6in), cutting just under a leaf node with secateurs or a sharp knife, then remove leaves from the lower third of the stem.
Place the cuttings around the edge of a pot filled with cutting compost or a mixture of 80% peat-free compost and 20% horticultural grit. They should be inserted to around two-thirds of their length and 2.5cm (1in) apart and watered in, before placing them in a sheltered position out of direct sunlight or in a greenhouse or cold frame.
3. Divide perennials
Mature perennials including rudbeckia, agapanthus, astrantia, cranesbill geranium, nepeta, hosta, delphinium and heuchera which may have outgrown their spaces or need perking up can easily be divided, which will give you two or more smaller plants out of one large one.
It’s best to divide perennials in autumn, after they have flowered and died down, or in spring when they are waking up and just starting to put on new growth.
After watering well, dig around the parent plant as wide and deep as you can go so as not to damage the roots. Once the plant is out, you can divide it with a sharp knife.
If you have large, fibrous rooted perennials such as day lily (hemerocallis) take two garden forks and insert them into the crown back to back, to use as levers to break the root mass into two sections, the RHS advises. This will allow you to further divide the plant.
Clumps of divided plants should be planted as soon as possible and watered in well, adding compost to the mix.
If you want to bring them to a bigger size before planting, pot them up individually, overwintering them in pots in a sheltered, frost-free space, the RHS suggests.
4. Swap plants
If you simply have too many plant divisions or have cuttings which haven’t found a place in your garden, find a fellow gardener to swap with – it could be a neighbour, a friend or family member or even someone you know at the local allotment who could potentially give you free plants which you didn’t have before.
5. Try layering
Layering plants is one of budget-conscious garden expert Anya Lautenbach’s favourite methods of propagation, which she describes in her bestselling book, The Money-Saving Gardener.
“When a low branch of a shrub or climber touches the soil, it can take root and produce a new plant (plantlet or offset),” she explains in the book.
Basically, layering is usually done in spring or autumn and it’s easier than taking cuttings as the layered stem takes root while still attached to the parent plant, which will look after it.
Layering is ideal for plants which are difficult to root from cuttings, such as rhododendrons, camellias and magnolias.
Just choose a young, flexible stem which is low down on the parent plant and bend it down to ground level, adding organic matter to the area, and cut away around 2.5cm (1in) of bark from the underside where the stem is going to be in contact with the soil (no more than a third of the way through the stem).
Make a 5cm hollow and bury the wounded part of the stem along 15cm (6in) of its depth in the hollow, leaving 15cm (6in) sticking out of the soil and secure it with metal wire or a hairpin looped over to stop it springing up.
Water it and keep in moist for the next few months and you may have to leave it for a year until you can see the shoot has rooted as it starts to branch out on its own. Then, you can dig it up and cut it from the parent plant before replanting it elsewhere.
