Plant Propagation

Seeds

The most common approach of plant propagation is collecting seeds from plants you already have in the garden. Some plants like lettuce and celery will just sprout if exposed to sunshine; others, like phlox and allium, only if they are entirely covered.

The majority of plants will gain from being started inside six to eight weeks before the last frost. There are a few plants that either do not like being transplanted or are sturdy adequate to take a light frost. Those plants are better off being planted straight outdoors. A couple of examples: peas, carrots, corn, beans, nasturtiums, morning glory, cucumbers.

Most perennials will significantly take advantage of being planted straight outdoors at the end of summer season. That will provide the plants the opportunity to experience their natural cold cycle and make them emerge more powerful and in their own time in spring.

Difficult seeds like nasturtiums, morning-glory and 4 o'clocks will sprout much easier if taken in warm water for 12 hours prior to planting.

When: Plant annuals in spring, perennials and biennials at the end of summer season, when the heat waned a bit.

Division

A prolific way to increase your garden stock is the department of mature plants Most herbaceous perennials really need dividing in order to remain healthy and flowering. Among those, a couple of examples: heuchera, daylilies, pampas yards.

Other plants, like daisies and bee balms will quickly spread if left to their own accord. Dividing them is a great way to control their growth and fill bare spots in your garden.

To divide the plant you can either dig it out totally and break the root ball into smaller sized parts or remove a part of the clump with a shovel. If you can do that, the advantage is that the remaining plant roots will remain undisturbed.

When: Divide spring flowering plants in the fall and fall blooming plants in spring.

Rhizomatous plants.

Amongst these: bearded irises, peonies, lily-of-the-valley, mint.

For small rhizomes, just pull out of the dirt and replant somewhere else. For bigger rhizomes, dig the plant out at the end of summer season after it finished blooming and cut up the root in 2-4 inch sections with leaf development at one end.

When: End of summer season or fall, after they have finished their vegetative cycle.

Layering

This works great with ground covers, strawberries, raspberries, and spider plant. Take a runner and tie it down to the ground with a pin. After the plant establishes roots you can cut it loose from the mom plant and move it someplace else.

When: whenever they choose to grow runners.

Cuttings

A lot of woody plants can be propagated like that, particularly roses, for whom this is the basic approach of proliferation. Other plants to be propagated by cuttings: butterfly bush, weigela, pelargonium, fuchsia, delphinium, forsythia, chrysanthemums, hydrangeas, African violets.

There are 4 basic types of cuttings: pointer cuttings (soft, green), stem cuttings (woody), leaf cuttings (leaf and petiole) and root cuttings.

For stem and tip cuttings, a minimum 3 inch length will guarantee the practicality of the plant. Wounding the cutting (making a longitudinal cut or squashing the bottom) will promote the plant to grow new roots.

Many plants, like mint, will grow roots if put in water. Other plants, like African violets and hydrangeas, will be happy to root if you stick a leaf with a long petiole in the dirt. For plants with big leaves, like hydrangea, it helps to cut up about half of the leaf to minimize the pressure on the developing root system to feed it.

If you have rooting hormonal agent, I highly suggest it.

When: For fall flowering perennials and annuals, start cuttings when the risk of frost has actually passed in spring. For spring flowering perennials, start the cuttings in the fall and safeguard them under cloches (a glass container would work just great) over winter season. It is extremely helpful to the plant to go through a winter in its natural environments, it produces a much healthier root system. This is particularly real for roses.

Bulbs, corms and bulbs

Some bulbs, like lilies, will start spreading out in a flaky pattern. Each scale with roots can be separated and start a new plant.

Onions can be vertically sliced and divided. For hyacinths there is a method called scooping: cut up the roots off a bulb and dig the central part right below them to expose the bulb layers. Place the bulb upside down half buried in a tray filled with damp sand. Place the tray in a dark warm area. In 12-14 weeks bulblets will start forming on the top of the big bulb. Plant the bulb upside down with the bulblets right listed below the surface area. Let the plant go through its vegetative cycle. The bulbs can be lifted and separated in the fall.

When dividing tubers, make sure to have at least one viable "eye" on each area.

When: In the fall, after the plants went dormant.

Dropping and stooling

Dropping includes pushing down and covering the majority of the plant stems with garden compost or good quality dirt, and await the plant stems to establish specific roots. The plants can be separated and replanted. This works for heathers and rhododendrons.

For the stooling approach mound up dirt high around the bottom of the plant, to give the stems an opportunity to grow roots. A couple of examples of plants for which this method works: lilacs, willows and dogwoods.

When: Drop and stool in spring, divide and cut in the fall.

Please keep in mind that some plants will effectively propagate through numerous of these techniques.

Here are some excellent resources for finding out more about plant proliferation:

American Horticultural Society Plant Proliferation: The Totally Illustrated Plant-by-Plant Handbook of Practical Techniques - Alan Toogood

Proliferation Basics: Tools Strategies Timing - Steven Bradley

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