Saltbush city limits

Winter 2017

This post is all about one of my favourite, drought resistant plants: Old man Saltbush. It's somewhat bulletproof in all regards, and only seems to grow bigger, in a drought. However, there are some care tips I've discovered since 2014, which considers their natural limitations. I've had five years to observe, how they've performed in our landscape.

The above is a hedge I planted, and discus in the beginning of a post called, All grown up. Six plants in total, and propagated from cuttings. During the wet years, they put on a stupid amount of growth. Which I used for chop'n drop mulch, regularly. In the dry however, they did this...

Late 2017

die-off starts to appear

Limbs are being sacrificed to save the plant. But I don't think this is Old man Saltbush's, natural survival trait. As I've had other plants, in more inhospitable conditions, avoid die-off, during the drought. It only happened to my regularly manicured hedges.

It's possible, my constant trimming of the hedge, from such an early age, forced more woody branching than it's natural form. When the branches from different plants entwined, it didn't allow proper circulation, which may have caused a weaker, more disease prone plant. That's part of my hypothesis, anyway. There's a range of contributing factors.

Over 2 years later

No green grass, and 1 survivor remains

As the drought bit harder, I gradually lost a plant, over a few seasons. But as this individual survivor demonstrates, when they're allowed to sprawl, unhindered - even when kangaroos graze it during drought, it continues to thrive. So it now spans the same width, of the three original shrubs.

Letting the rogue one, go (mostly unhindered) was inspired by the resilience, I'd seen in other individual Saltbush, around the garden.

Blue, sprawling Saltbush

(left and right)

There's actually three Saltbush, in this view - a smaller one, hidden by the top-left plant. I occasionally trim these for mulch, but since the drought, I rarely do now. When allowed to sprawl, they find the desirable shape, to lessen the chance for disease to weaken branches.

Traditionally, Saltbush hails from flat, arid landscapes. But even on slopes, they have a few tricks to help reduce evaporation around the root zone.

 Ignore the plant underneath the blue line,

it's a sprawling, Eremophila glabra, "Kalbarri Carpet"

Where the ground falls away from the main trunk, Saltbush sends out branches to close the gap again. I actually trimmed this lower section, to give circulation to the bromeliad, growing underneath. Since it died however, I've stopped pruning. The Saltbush is now filling in the space, to match the fall of the land.

It gives a peak, at the amount of leafs, which are dropped underneath too. This further aids in cooling it's root zone, and reducing the chance of evaporation. So it doesn't matter how the land falls, Old man Saltbush, hugs as close as possible to the ground. I really admire, how this plant adapts to increase it's chance of survival.

x2

This is the two Saltbush, growing side-by-side. Both are from propagation, but the one on the right, was planted a few years later. Both seem healthy, and unaffected by each other. The younger bush was establishing, as the ones in my hedge, were slowly dying. This is why I propagate.

These two specimens, are about two metres apart. I'm happy with that distance. Given their spread, can reach three metres wide (or more) it's even possible to space further apart too. I'll be watching to see how the two shrubs effect one another, as the younger one, puts more girth on. I suspect, there won't be any issues, but time will be the ultimate judge.

Winter 2014

Here's what the same location looked like, five years ago. It demonstrates, the capacity for Saltbush to fill in space, relatively quickly - despite the lower rainfall, and hot growing conditions. This plant is invaluable, when you don't have extra irrigation beyond establishing.

There are few plants, with as much foliage as Saltbush, to achieve this kind of vigorous growth, in such a short time. Trust me, I've tried to find others! There are a couple, with one or two similar traits, but not with the same dense foliage, Saltbush can manage in a drought.

Originally purchased online, from a nursery in NSW 

(different State to ours) 

I wasn't entirely sure, if the original nursery grown cuttings, would take to our conditions. But this is the grand-daddy, of all my Saltbush. First in ground, and lived to exceed my expectations. Because it's really had the worst location to establish. I've lost a lot more expensive plants on this slope. It's just so dry here. You can even see, the weeds won't grow. But it's still become a monolith.

This is the most neglected, and least pruned by me and the kangaroos. Yet still managed to sprawl, a whopping 4 metres wide!  It's living mulch, I never attend now. All on a slope, I can't get anything else to grow. In fact, the plants above this bush, are probably only alive, because of it's capacity to adapt and fill out the space. The soil would be baking in that spot, otherwise.

Top pick

This is my favourite Saltbush. Can I have a favourite? It's close to hilltop chicken coop, and I've taken a lot of successful cuttings from this plant. It has lucky vibes or something special, which contributes to the success rate. I really should start propagating this plant again.

I've read that Saltbush can be a long lived perennial, and others state, it grows woody and dies relatively quickly. I've experienced both. It really comes down to the conditions, the plant is kept, which contribute to it's longevity. I'll summarise my tips for longevity - that work in our location:

• Can be pruned by animals or humans, but not continually
• Prefers to spread, unhindered by other plants
• Avoid heavy pruning in a drought, as the plant needs leaf drop, to preserve it's root zone
• Avoid irrigating with grey water, containing ingredients that alter soil pH (ie: borax)

Three years old (2017)

Saltbush can handle a range of soil PH (4-8). The more outside these ranges, however, the more it will struggle - likely be attacked by pests, and experience some die-off. Which is something I cannot rule out, happening to my original hedge, either. Pest damage, that is.

The hedge was planted near a cement verandah. While cement doesn't normally effect PH, in a significant way, I have emptied mop buckets over the edge. Even mild chemicals, can release ingredients in the cement and effect the soil PH - over time. Enough for pests to eventually build numbers, and take advantage in the drought. It didn't happen immediately. It took time, and a series of unfortunate events.

Yellowing leafs, can be a sign of Leafhopper damage

this is my remaining hedge survivor

Scale, Leafhoppers and Borers, are known pests to Saltbush. I've noticed significant presence of these pests, in other nearby plants. My lemon tree, for example. Given the right conditions, these pests can attack Saltbush and cause significant die-off too.

Since my large sprawling plants, have never shown any indication of stopping (or pest infestations) I can only conclude my hedge of close plantings, increased the likelihood of death by pest overload. It's been observed in large plantations of Saltbush, for stock fodder too. Events are episodic, depending whether the climatic conditions, favour the pests.

Being mindful of how I was treating my Saltbush, enabled me to consider the best natural defenses I could give the remaining plants. Especially in the extremes, I was growing them in. Compared to most plants, Saltbush is incredibly bulletproof. It can withstand a lot of punishment. But also has limitations, which can be exploited by pests, in the right conditions.

Formerly used Satlbush prunings, for chop and drop mulch

I don't want to give the impression, Old man Saltbush can never be touched, with a pair of pruners though. During wet seasons, it's a great way to stop branches breaking, under load of water. It also increases air circulation, so the woody material doesn't develop fungal infections. In the right conditions, regular pruning can actually extend the life of the plant.

When the dry bights, however, a different approach needs to be adopted. Because pests love nothing better, than a large food supply, all lined up in a row. Letting the plant, spread out and do it's own thing (by preserving foliage) will make it less likely to get disease, and become an invitation for pests. At least that's been my observation, to date. I'll still lop off a branch (or two) in the dry, if it's getting in the way. But I don't treat it like a manicured hedge, any more.

Do you have a plant, that comes close to bulletproof in the garden - or in your region?