It is easy to recognise an Orchid as tender, a warmth loving plant which requires a nice indoor home. It's less easy to be so clear when considering planting some of our common garden plants and shrubs. The problem is if you don't know  the frost hardiness rating of a plant you don't know where to plant it in your garden, or whether it will survive one of our winters.

The shrub in the image below left is Nandina domestica, common name heavenly bamboo, although it is not a bamboo at all, it is a lovely garden shrub with fine delicate leaves which appear bronzed or tinged red on some varieties. It makes a really good addition to a shrub border but how hardy is it?

Under the old hardiness rating system it was classified as *** which is hardy but in reality it only really likes temperatures down to around -10 degrees C and  dislikes exposed gardens and chill winds which can leave it looking in a very poor state at the end of the winter. The old system of hardiness rating was a bit of a blunt instrument with just 4 categories to cover tender to fully hardy. The new system of frost hardiness rating devised by the RHS in 2012 and launched this year has 7 catagories and so allows for more information around the hardiness rating.

Curiously I cannot find Nandina domestica classified under the new hardiness rating system, even though all the RHS merit plants are meant to have been re classified under the new rating, most web sites including RHS say "frost hardy but needs sheltered position." 

I suspect looking at the new classification Nandina domestica will be not considered fully frost hardy but H4 which is only down to -10 and with reservations with regard to garden sites and exposure.

The new system of hardiness rating should make the position clearer. A shrub such as Nandina domestica would be better described as H4 and inform the buyer to bear in mind it's slightly tender nature, and to plant in a sheltered spot, and not at all in an exposed garden.

The RHS has tackled the problem of our frost hardiness rating system although I guess it will take another 12-18 months to determine if it is working out as planned. For more information about the old and new system of frost hardiness follow the link

Sedums are one of the easiest plants to propagate and look great from late summer right through to the winter frosts. Some plants particularly  herbaceous ones can look a bit sad but this time of year but not Sedums. All through the summer Sedums are loved by bees and butterflies and during the summer look like bee magnets. Frosted Sedum flower heads look just magnificent.

Sedums are remarkably easy to grow and propagate. In the summer, when cutting some back plants for the Chelsea chop, I used the cuttings to propagate more plants. I did this by simply pushing the cuttings into the soil alongside the mother plant and they grew. There is more information as to just how easy this is on the Sedum pages. Quite often when propagating plants from cuttings, precise treatment is required, stripping off the leaves and putting into a propagator or in a pot with a firmly sealed poly bag to create the necessary warm and moist atmosphere; but not Sedums,. They are very easy and a good place to start if you want to begin to propagate your own plants for free. 

In the autumn, a full stem was accidentally snapped off,  and since it was looking so lovely I brought it inside to put  into a vase where it kept it's flower head for several weeks and has now started sprouting. I  may try planting the plantlets up and leave over winter in a frost free place see if it takes further root. Looks interesting!

This time of year the weather creates some great effects.  

Over the weekend,  the hard frost, followed by sun on the pond, created a great smokey atmosphere. The grasses appear as if beaded in the frost and heat from the sun caused steam to waft up and around as if magic.

Grasses and ponds change so much over the seasons there is always something interesting to see. Grasses are good value; they add movement see the image (far left) of dancing Stipas, changing colour through the season and looking good with Alliums and Achillea (centre image)  and  in the winter lit up like sparklers (below right.) 

Most grasses are easy to grow and mix well in borders, for  more advice and tips on easy to grow grasses