25/10/2026
🌶️ MAD MONDAY: NO-TILL ISN’T A RELIGION, PEOPLE! 🌶️
Welcome to Mad Mondays — where horticultural wives’ tales get called out and opinions come with absolutely no apology.
Bloomer friends, put down your pitchforks for a moment. We need to have a little chat about no-till gardening. 😂
Now, before someone faints into their compost heap, let us be clear: we are absolutely in favour of healthy soil. We love beneficial microbes, worms, organic matter and everything that contributes to a thriving growing environment. We’re not here to wage war on soil biology.
But here’s the thing… what works beautifully for one crop doesn’t automatically work for dahlias. And we reckon this is a conversation worth having.
🌱 FIRST, LET’S TALK ABOUT WHAT’S UNDERNEATH.
One of the most common approaches to no-till gardening is to lay cardboard over an existing lawn or patch of grass, pile some compost or mulch on top, and plant into the resulting bed.
Sounds easy, doesn’t it?
Unfortunately, grass didn’t get the memo that it was supposed to die quietly beneath that cardboard. Some grasses are remarkably persistent, and invasive, creeping varieties can send runners through beds, reappear at the edges and compete with your plants for water and nutrients.
Cardboard can suppress grass, but it isn’t a guaranteed solution. If you’re starting a new dahlia bed, dealing with persistent grass and its roots before planting can save you a whole lot of grief later.
And then there’s the soil itself.
Cardboard is not a growing medium. A THIN layer of compost is not a substitute for a properly prepared root zone. And a pretty garden bed on top does not guarantee good soil underneath.
If the existing ground is hard and compacted, adding organic matter to the surface alone can take years to improve the soil beneath that initial layer. The worms, fungi and microbes may be happily working away in your lovely new compost, while the compacted ground underneath remains a challenge for developing roots.
And for dahlias, that matters.
🌸 1. DAHLIAS ARE RELATIVELY SHALLOW-ROOTED — AND THAT CHANGES THE GAME.
Dahlias do much of their feeder-root activity in the upper layers of soil, while their tubers develop beneath the crown.
Those roots need access to moisture, nutrients and oxygen. They need a suitable growing medium in which to establish, feed the plant and support its growth.
When a no-till bed consists of cardboard over compacted ground with only a relatively thin layer of compost or topsoil, the available rooting depth may be inadequate for the plant’s needs.
And remember, we’re not just growing a pretty green plant here.
We’re growing dahlias that need to stand upright, produce strong stems, carry quality blooms and develop a healthy crown and tuber clump for next season.
If the growing layer is too shallow, poorly structured or insufficiently supported, plants may struggle to anchor themselves securely. Tall plants carrying large blooms can become unstable, particularly in wind or wet weather.
And if the root zone is compromised by compaction, poor drainage or inadequate growing medium, tuber development can suffer too.
A dahlia needs more than a place to sit. It needs a suitable soil profile in which to establish, feed and anchor itself.
🌸 2. YOU CAN’T COMPOST YOUR WAY OUT OF COMPACTION OVERNIGHT.
We love compost. We love well-rotted manure and organic matter. They have an important role in building soil structure and fertility.
But simply adding more to the surface doesn’t automatically fix a dense, compacted layer beneath it.
Shallow cultivation can help break up a compacted surface layer and allow organic matter to integrate more readily with the existing soil.
Deeper aeration, where appropriate, can help relieve compaction and improve the movement of air and water through the soil without completely turning the entire bed over.
The aim isn’t to dig for the sake of digging. It’s to identify what your soil needs and address the problem.
Some no-till gardeners might argue that any cultivation defeats the purpose. We respectfully disagree with turning a useful gardening method into a set of commandments.
No-till is a soil-management approach, not a moral achievement. You don’t win a medal for never picking up a digging fork!
🌸 3. SHALLOW ROOTS MEAN THE SURFACE MATTERS. A LOT.
Those upper soil layers are particularly important for dahlias. They need a suitable balance of moisture, nutrients and oxygen, along with enough depth and structure for roots to develop and help support the plant.
A thick layer of mulch can be useful. It helps conserve moisture, suppress weeds and contribute organic matter as it breaks down.
But mulch isn’t a magic fix for every problem.
Too much mulch at the wrong time can delay spring soil warming. In Australian growing conditions, timing matters. We want the soil warming and the growing season getting underway, not our planting rows tucked beneath a winter doona when it’s time to get those dahlias moving!
And while we’re talking about moisture, good drainage remains essential. Retaining moisture is useful; keeping the root zone waterlogged is another matter entirely.
🌸 4. SOMETIMES, YOU ACTUALLY NEED TO GET YOUR HANDS DIRTY.
At Brundee, we’ve been preparing our beds by digging out the paths and hilling that soil up into our growing rows.
We’re creating a more suitable growing profile, improving drainage and giving our plants a better environment in which to establish.
We’re not interested in disturbing soil unnecessarily. We want to protect its structure and encourage healthy soil biology wherever we can.
But we’re also not going to stand back and admire a gardening philosophy while our plants struggle in unsuitable ground.
Sometimes the right answer is to remove persistent grass. Sometimes it’s to address compaction. Sometimes it’s to improve the depth and structure of the growing medium. And sometimes it’s to leave the soil alone.
The trick is knowing which situation you’re dealing with.
🌸 5. AND WHAT ABOUT THOSE TUBERS?
This is where we think dahlia growers need to pay particular attention.
We invest time, money and an extraordinary amount of effort into selecting good varieties, growing strong plants and maintaining quality stock.
Yet we can overlook the very environment in which those plants are expected to develop their next generation of tubers.
If a dahlia is growing in a shallow layer of loose material over hard ground, it may have limited room to establish and develop properly. If the plant is poorly anchored, it can become unstable. If the root zone is compromised, the plant may not reach its full potential, including its potential for healthy tuber development.
Of course, tuber production also depends on variety, plant health, growing conditions, moisture, nutrition and the length of the growing season. No single soil-preparation method guarantees a bumper clump.
But we shouldn’t handicap the plant before it has even had a chance to grow.
If you’re investing in quality dahlias, give them a growing environment worthy of that investment.
🌸 SO, ARE WE AGAINST NO-TILL? ABSOLUTELY NOT!
There is plenty to admire about protecting soil structure, reducing unnecessary disturbance, retaining moisture and feeding the organisms that make soil function.
But there’s a difference between minimising unnecessary disturbance and refusing to intervene when your soil genuinely needs it.
We need to understand our soil, our climate and the crop we’re growing. We need to consider invasive grass, compaction, drainage, the depth of our growing medium and the physical support our plants need.
And we need to remember that a method developed around growing vegetables in a mulched bed doesn’t necessarily translate directly to growing tall, top-heavy dahlias.
Healthy soil is the goal. Strong, stable plants are the goal. Beautiful blooms and healthy tubers are the goal.
And if achieving that means getting a little dirt under our fingernails, you’ll find us out there with a digging fork. 😉
Just remember: your dahlias don’t care about your gardening ideology. They care about the conditions you give them. 😂
