Waste not want not is a motto every good gardener should take to heart. Propagating your own plants, swapping bits with other gardeners, helps extend your garden flower-power. Plants reproduce largely by seed: here we deal with non-seeding (vegetative) propagation.

Take cuttings late summer: divide and layer spring or fall. Buy and plant a blue Nile lily.

Needs list: 1 root agapanthus.

Time budget: 2 hours in 2 weeks

Mid March weather/soil

The second half of March is usually rather dry – drier than April on average. However, soil-water levels are still high and the soil basically deadly chilly: bursts of warm sunshine do little to raise the soil temperature: be patient 2 more weeks.

Flower of the Fortnight

Herbs are an essential part of every self-respecting garden these days. Most of them have been in cultivation for hundreds of years, and most originated in the Mediterranean basin: translated into gardening terms that means they nearly all need a sharply draining, preferably sandy soil and a position in full sun.

The two we show are chives and balm.

Balm is a hardy perennial, sweet-smelling and closely related to mint. Like mint, it can get out of hand. Chop it back ruthlessly if it does.

The other is chives, a perennial onion with tiny bulbs, grown for its hollow, tubular leaves which have many culinary uses. Cover the herb garden with glass or clear plastic sheeting in hard winter areas.

Groundwork

Keep persevering with your compost bin. Compost does not always come right first time, but it’s important that you get the hang of it. Once you’ve got it working it will consume most of your garden waste, and turn it into valuable top dressing and mulching material. If the compost is too wet, soggy and slow to decompose, it needs better aeration. Try a 3-in. Plastic mesh netting container inside your bin, leaving a 3 in. air space between the netting and the outer framework. Alternatively, drill holes at staggered spaces in the wood container.

If you really want to make the finest compost in your street, there are dozens of good, usually cheap, books on the subject. Now look at naturalizing. Weeds are plants that naturalize themselves in your garden. Get rid of the weeds and you can get many of the plants you like to naturalize there instead. Honesty and wallflowers should be starting to naturalize already: that’s what all those self-sown seedlings are doing. Bulbs naturalize easily. Plant indoor hyacinths outdoors after flowering and leave them to naturalize, they’ll look great.

Project work: propagation and other gardening skills

Propagating your own plants is probably one of the most satisfying and creative of all aspects of gardening. There are two main types of propagation, sexual and vegetative. Sexual propagation just means sowing seeds: unless you want to go in for a plant breeding programme. You already know how to increase plants from seed, you’ve been doing it for nearly a year now. Time to move on to the vegetative methods: we’ve touched on some of them earlier.

There are 4 main methods of propagating plants vegetatively: cuttings, layers, division and grafting. Let’s look at each. Cuttings: two types; hardwood and softwood. Hardwood cuttings are for shrubs and softwood cuttings for pelargoniums. Cut the piece you want to propagate with a sharp knife: make the cut just below a leaf-joint (known as a node). Strip off the lower leaves. Dip the cut end in hormone rooting powder; tap off surplus powder. (Funny stuff this hormone rooting powder: just a little helps roots develop: too much positively prevents them forming; so use it sparingly.)

Plant in a V-shaped trench with sand at the bottom or in a dibbled hole in a peat pot filled with soilless growing mix.

Division, at its simplest, is just splitting up root clumps, mainly of herbaceous plants. Cut dahlia tubers down to old stem with a sharp knife, leaving an ‘eye’ – growth bud, on each piece. Remove small bulbils from corms, bulbs. Plant up, grow on. Layering, the simplest method of all. Simply peg long shoots into the ground and cover with soil. Works for plants like periwinkle and most shrubs. Grafting is transferring the upper, fruiting or flowering part of one plant onto the rootstock of another.