Meaning of ‘propagation’ – human-mediated production of plants; as opposed to ‘reproduction’ which is the plant’s natural processes without human intervention.
Seed propagation – producing plants in a human controlled manner from seeds
Vegetative propagation - producing plants in a human controlled manner from parts of a plant.
Seed propagation – advantages/disadvantages Guarantee only applies to vegetable seeds. Guaranteed germination rates and disease free Slower to maturity than vegetatively propagated plants. Storage – most seed can easily be stored for some time Seeds for single colour of some flower varieties may not be available. Choice – a huge range of seed available Takes time and space to grow from seed to plants ready to plant out. Large volumes of seed – cheap way to produce new plants Open pollinated plants may not come true from seed The ability to breed new varieties Disadvantage Advantage
Tender perennial – Heliotropium aborescens (Cherry Pie plant) usually grown as an annual
Hardy perennial – Liatris spicata (Gay Feather)
Vegetative propagation – advantages/disadvantages Smaller volumes in general – but NB - tissue culture. Ability to adapt plant to environment using rootstock choice e.g. Malus Gradual loss of juvenility unless care of parent plants is very skilled. Speed to maturity is much quicker. Time – each plant has to be individually propagated. The only way to reproduce sterile varieties such as Vitis vinifera ‘Thompson’s Seedless’ Cost – requires skilled labour and aftercare. Uniformity – each will be exactly the same. Little chance of a new variety arising. Monocultures are susceptible to disease. True to type – each is a clone of the parent. Only way for some varieties e.g. variegation. Disadvantages Advantages
Wisteria sinensis – perennial climber; desirable flower form and colour not reliable from seed. Long juvenility.
Petunia ‘Surfina’ ( P. hybrida x P. pendula ) – will not reproduce from seed; PBR applies.
Mallus domestica ‘Bramley’s Seedling’ – all apple varieties are produced vegetatively by grafting. This enables reproduction of the variety characteristics and also the control of the size of the eventual tree by choice of rootstock.