Sexual and Asexual Propagation – What’s the Best Way to Propagate Your Plants?

There are a variety of ways to reproduce plants - from the age-old method of planting seeds to modern techniques like tissue culture. Every technique has its pros and cons, and the best method often depends on the plant species and the grower’s goal.

What Is Sexual and Asexual Propagation?

Plants can reproduce in two major ways:
Sexually (through seeds) and asexually (through cloning).

Sexual Propagation

Sexual propagation involves the union of genetic material from two parent plants. The most common example is seed production, although some plants (like ferns, mosses, and fungi) use spores instead.

How it works

A plant produces flowers that contain male and female parts.
Pollination occurs naturally via:

• wind
• insects (bees, wasps, butterflies)
• birds
• manual pollination by the grower

Once pollinated, the plant forms seeds that contain new genetic combinations.

True-to-Seed vs Not True-to-Seed

Not all plants grown from seed will look or behave like the parent.
Some are true to seed (they reliably produce uniform offspring), while others are not - especially hybrids, which often revert back to earlier genetics.

Self-Pollination

Some plants can pollinate themselves without outside help. These include:

• tomatoes
• peas
• beans
• lettuce

Self-pollination is great for seed-saving because the plants are more likely to stay genetically consistent.

Why growers use sexual propagation

• To create new hybrids or cultivars
• To improve traits like fruit size, colour, disease resistance, or growth speed
• To grow large numbers of plants cheaply
• To explore genetic variation (“phenotype hunting”)

Commercial breeders and hobby growers often sow seeds specifically to find stand-out phenotypes - a dwarf version, a heavy yielder, a unique colour, or a more disease-resistant plant. Once found, that plant can be used as a parent or a clone.

Asexual Propagation

Asexual propagation produces genetically identical clones of the parent plant.
This includes:

• cuttings (softwood, hardwood, leaf, or root)
• division (e.g., rhubarb, hostas, grasses)
• grafting and budding (common for fruit trees)
• layering
• tissue culture / micropropagation

Why growers use asexual methods

• Guarantees uniformity: every plant is identical
• Preserves a specific genetic expression (a perfect fruiting branch or a rare colour)
• Faster time to maturity - cuttings often grow quicker than seedlings
• Allows commercial growers to produce thousands of plants from one elite “mother plant”

Examples in NZ include:

• Braeburn apples (grafted)
• Feijoas (often grafted or layered for consistency)
• Blueberries (usually tissue-cultured for disease-free starts)
• Heirloom tomatoes (cuttings for rapid cloning)
• Hydrangeas, figs, rosemary, lavender (commonly propagated by cuttings)

Asexual propagation provides the reliability growers need to meet retail expectations and produce uniform crops year after year.

How Do Growers Choose Which Method to Use?

Commercial growers typically choose asexual propagation when:

• uniformity is essential
• the cultivar has unique traits worth preserving
• the plant doesn’t grow true to seed
• speed and consistency matter
• diseases need to be controlled (tissue culture creates clean stock)

Seed propagation is chosen when:

• genetic diversity is desired
• breeding programs are underway
• cost needs to be kept low
• plants naturally grow true to seed
• producing large quantities quickly is important (e.g., lettuces, brassicas)

What About Home Gardeners?

Both methods work no matter the scale - from large orchards to a small garden in Aotearoa.
Here are some simple guidelines:

Use seeds when you want:

• variety and experimentation
• cheaper starts
• to grow annual crops such as tomatoes, basil, lettuce, beans, and flowers

Use cuttings or cloning when you want:

• to copy a plant you love
• to maintain a rare or heirloom variety
• to ensure consistent fruiting (e.g., citrus, berries, grapes)
• faster growth compared to seed-grown plants

Conclusion - Which Method Is “Best”?

Neither method is universally better - it depends entirely on your goal.

Choose sexual propagation (seeds) when:

• breeding new cultivars
• experimenting with genetics
• growing annual vegetables
• cost and quantity matter

Choose asexual propagation (cuttings, grafting, tissue culture) when:

• you need identical plants
• you have a perfect “mother plant” worth preserving
• the species doesn’t grow true to seed
• you want faster, more reliable production

In short:
Seeds are for variety.
Cuttings are for consistency.