Eremophila or emu bushes would have to be one of the most useful group (or genera) for dry land gardening. I often talk about and suggest them for planting for a number of reasons.
Most species will happily grow on a sub 250mm annual rainfall. All the rest will happily grow on sub 400mm annual rainfall. This means in practical terms that you could choose species that would not need watering at all once through the first summer or at most as little as monthly watering.
Almost all species are resistant to frost. I mean seriously frosty. I can think of a project in Loxton (known for it’s frost compared to other Riverland towns) two years ago where the day after planting minus 9 degrees Celsius was recorded. Were the emu bush worried? No! In fact the whole planting known as “Mill Corner” is as pretty as a picture and not many days go by when I don’t receive samples with the comment “I just have to have one of these”.
At the other extreme, heat is not a problem. In full sun with two weeks of 40 degree Celsius plus and they just carry on as if it’s all normal. I suppose it is for an emu bush!
Emu bush also happily put up with some of the worst soils on earth. Seriously limey with over the top high pH. Soils that would turn a Grevillea instantly yellow with an iron deficiency, emu bush simply thrive on. I’ve seen them on stony cliff tops, baked and cracked clays and shale hills. I’m talking about Mad Max country side. In fact many different emu bushes come from around Broken Hill where Mad Max was filmed.
You would think that with a tolerance to such extremes that too much water could be a problem. Well it is for many species but we have two in the Riverland that occur on the flood plain and Eremophila bignoniiflora and E. divaricata are more than happy to be completely submerged for short periods. I know this is taking flood irrigation to the limits so don’t try this at home!
I know what you are thinking. Such a hardy plant just has to be ugly? NO WAY. With bird attracting tubular flowers in a colour range that quite literally covers all shades of the rainbow including white they will fit with any colour co-coordinated garden. Many species flower all year round and with a few species it is feasible to have a wide range of colour all year round. The form and foliage on many species is very attractive even without flowers.
If emu bushes have a down side it would only be that you need to remember not to water. Many species really are quite happy on natural rainfall or monthly watering at most. The only maintenance that would be required is a light prune each year when they finish flowering and even this can be omitted for plants doing it really tough.
While emu bushes respond well to extra water and fertiliser this will often produce soft growth, that if you over do it, insects will find attractive. So the message is if you leave them alone they will grow on their own. This in turn will leave you more time in your garden to actually enjoy it.
This article first published in the Riverland Weekly © October 8, 2009.