Last year I ran a series on explaining various different gardening terms. This series proved very popular and so it is making a return in 2011. To catch up on the words you may have missed in 2010, check out my two recap articles, Part 1 here and Part 2 here.
Read the February article here.
Read the March article here.
Words for April – dieback, cultivar, runner & layering
Dieback is something that is very common amongst Australian native plants when pests and diseases from outside Australia invade your garden. It basically causes the tips of branches or new shoots to die and this then spreads across the plant generally until it dies or the dieback is treated. Generally dieback is a disease, basically a form of mould, which means it can be spread by water, uncleaned gardening tools and various pests and is a real problem in many native area’s around Australia.
A cultivar in the gardening sense is almost another way of saying a man made plant, which in some ways doesn’t actually make sense. A cultivar refers to the method by which horticulturalists often reproduce new plants. Rather than planting seeds and waiting for them to grow, they cut off part of a plant and get that to grow roots and take hold, by various means and in this sense, it is not natural reproduction but man made. Sometimes the word cultivar is applied when two varieties of plant within a species are joined together (like a hybrid) and used to create a new ‘cultivar’ within that species of plant.
Many plants grow by sending out things called ‘runners’. Runners are shoots from the plant which generally grow along the ground (or sometime another surface), creating new roots as they grow. Many grasses grow in this fashion, sending out new shoots which establish themselves with roots as the grow. For something to be considered a true runner it does need to produce roots because what runners often do is, in effect, create new plants. When a ‘runner’ shoot has sufficient roots, you could separate it from the original plant and it would continue to survive.
The term layering can be used in a few ways but the main one is in regard to a propagation technique. Basically, layering is when you take the flexible stem of a plant, bend it over and cover it with soil, encouraging the buried stem to produce roots due to its proximity with the soil. Once this section has grown roots and taken hold, you could trim the stem off the original plant and have a whole new separate plant. Not all plants are suitable for the layering propagation technique.