Why Aren’t All Grasses Grown From Seed?
Many of the grasses sold on the market today cannot be propagated from seed. Some of these grasses are sterile hybrids, which means that the seed is not viable. Calamagrostis ‘Karl Foerster’ is an example.
However, more often it is a case of a specific ornamental grass maintaining its characteristics only by being vegetatively propagated. Many of the more decorative grasses have a special trait such as a strong red leaf colour (eg. Panicum virgatum ‘Shenandoah’) or a larger size or a more beautiful flower. A grower noted this and decided that such a trait was worth preserving. So it was done by vegetative propagation – by separating or dividing the parent plant into many smaller plants, over and over again. Seeds from Panicum ‘Shenandoah’ will not produce plants that look like it, rather it is likely to produce plants that look like Panicum virgatum, a much greener plant. The only way to obtain more Panicum ‘Shenandoah’ plants is to divide it.
It is very easy to tell at a glance which grasses are vegetatively propagated. Its in the name. Simply look for a name in single quotes, for example, Panicum virgatum ‘Shenandoah’ or Festuca glauca ‘Elijah Blue’. Panicum virgatum is the species name and ‘Shenandoah’ was the name given to that particular plant. Vegetatively propagated grasses will always have a uniform look in the landscape, that is to say that they will all be approximately the same size, shape, height and colour.
You may have noticed how many cultivars of Miscanthus sinensis exist. That is because its seed produces highly variable plants. Growers have noticed this and selected a number of beautiful plants. The variation is amazing! Hence there are over one hundred distinctly different Miscanthus sinensis cultivars available on the market today.
Grasses without the single quote in the name are often grown from seed. These seed grown grasses will vary slightly in colour and size. For example Festuca glauca will vary from blue to blue-green. Some may be bushier, others more upright, etc. Seed grown plants are often less expensive to produce, hence they are priced lower than the more labour-intensive divided plants.
So if you are doing a mass-planting of a single grass, give some thought to how important a uniform look is to you. If you are considering the less expensive seed-grown plants, feel free to ask us about the plant's uniformity, as some grasses show little variation from one plant to another.
Every once and awhile plants are mislabeled. With the huge number of plants on the market this is unavoidable. Pennisetum alopecuroides 'Hameln' appears to have been a victim of this, as some plants labeled as P. ‘Hameln’ are proving to be much larger for some people than for others. It should be that all P. 'Hameln' are the same size. We take very seriously the maintaining of the correct name. In the case of P. 'Hameln' we do in fact have the dwarf variety.