Sometimes when I am giving a talk, the participants will tell me that they don’t bother trying to grow plants from seed anymore. It’s too hard, it never works, the slugs get them etc etc. It is true that there are lots of things to consider on this topic and I am keen share some of what I have learnt on my seed sowing journey. Before starting it is good to understand the type of plants that can be grown from seed and and a bit about their life cycle .
When I studied horticulture I found some of the terms confusing – hardy, half hardy, annual, perennial and other words got mixed up in my head. I found it helpful when I finally grasped what it meant and I am hoping this will help you understand better too. All the terms here relate to how long a plant lives under its ideal weather conditions.
Annuals – germinate, grow, flower and set seed in one season, then die – that means you need to grow them from seed every year. They can be divided further into hardy, half hardy and tender but that relates to the weather rather than the life cycle (more on that in ‘Considering the weather’ post). Examples are Cosmos, Cornflowers, marigolds, lettuce and radish – also many of the spring and summer bedding plants that are available every year at the garden centre. Biennials – germinate, grow vegetatively in year one, flower and set seed in year two, then die. Because of their nature the biennials we grow in Ireland are usually frost hardy as they have to survive a winter before flowering. Examples are Hollyhock, Foxgloves (although some are perennial), onions and garlic.
Perennials – usually germinate in year one – some also flower in the first year, some in second, some trees don’t flower for many years. Some perennials are short lived only surviving for 2 to 3 years, others survive for many years. Some are hardy and others are tender (more on that in ‘Considering the weather’ post). Some stay green all year round (evergreen) and others die back in winter(herbaceous). Some perennials can be tricky to germinate, some have complicated protective mechanisms that need to be overcome in order for the seedling to appear (a topic called dormancy) – it is not something to worry about, a little knowledge about what to do is all that is needed – a topic for another day! It can be a fun challenge to try something harder once you have succeeded with the easier seeds.So if you are thinking about giving seeds another go, have a think about what you would like to grow and check out if it is annual, biennial or perennial and then head off to the garden centre.