The "Bowling Alley" Mistake: How to Fix a Flat Backyard and Save Your Retaining Wall

The Dilemma

A homeowner recently asked:

I'm designing a modern subtropical backyard on an 800m2 block, but I'm worried my Emerald Ficus is too close to the retaining wall, and I want to avoid the 'bowling alley' look with my lawn.

The GardenOwl Diagnosis

The Assessment

You are working with a solid 800m2 block in Penrith, which is a blessing for space but a challenge for climate. You want a 'Modern Subtropical' look—lush greens, big leaves, and a resort vibe. You have a hand-drawn plan (which is already better than 90% of homeowners), but you are staring down the barrel of two classic problems that severely impact your curb appeal and structure. These landscape design mistakes include The Linear Corridor Effect (The Bowling Alley), a layout that looks like a landing strip, and a tree that is about to cost you ten grand in structural repairs.

The Trap: The Foundation Killer

Let’s address the elephant in the room first: that Emerald Ficus (Ficus hillii 'Flash'). You mentioned it is one meter away from your western retaining wall.

I’m going to be blunt: It has to go.

I know it hurts to cut down a mature tree. But Ficus roots are aggressive, hydraulic drills. They hunt for water with zero respect for masonry. A root barrier at three feet (one meter) is just a delay tactic. Those roots will dive under it or hop over it, and eventually, the hydrostatic pressure will blow out that retaining wall. I have seen this happen too many times—you end up paying to rebuild the wall and remove the tree later anyway. Save your money and do it now.

If you want to understand the mechanics of how trees wreck hardscapes, read about why retaining walls fail under pressure.

The Solution: Breaking the "Bowling Alley"

Your sketch shows deep planting beds (up to 2.5 meters), which is excellent. Most people make them too shallow. However, you are suffering from the "Bowling Alley" effect because your lawn is a perfect, straight rectangle. It shoots the eye straight to the back fence, making the yard feel faster and smaller.

The Fix: Curve the Negative Space Don't just think about where the plants go; think about the shape of the grass.

1. Swell and Shrink: Curve the bed lines so the lawn widens in some areas and narrows in others. This creates "rooms" and forces the eye to slow down and scan the garden rather than rushing to the end.
2. Solar Control: You are in Penrith. In January, that is basically a kiln. Do not put a Brush Box in every corner—they get too big and will shade out your lawn. Instead, place one single Brush Box on the western boundary. This is a tactical move. It blocks the brutal afternoon sun from hitting your deck and house, potentially dropping your indoor temps by 10 degrees. For more on managing western sun, check out our guide on shading west-facing fences.

The Plant Palette: Lush but Tough

Since you are in a high-heat zone, you cannot use delicate rainforest tropicals. They will fry. You need plants that look lush but act like cacti. Here is your "Bulletproof Subtropical" list:

• Structure: Strelitzia nicolai (Giant Bird of Paradise). These give you that massive banana-leaf look but are much hardier. Use them in the corners to blur the fence line.
• Mid-Layer: Mass plant Philodendron 'Xanadu'. Unlike the sprawling split-leafs, these grow in tight, tidy clumps. They look modern, clean, and tolerate the heat once established.
• Screening: If you need to hide a neighbor, use Bambusa textilis 'Gracilis' (Slender Weavers Bamboo). It shoots up to 20 feet but stays in a tight 3-foot footprint.
• Color: Get your color from foliage, not flowers. Cordyline 'Rubra' or 'Negra' adds deep purples that pop against the green Viburnum.

Pro Tip: Avoid "onesies." Don't buy one of everything like you are collecting stamps. Buy in groups of 3, 5, or 7. Mass planting the Xanadu under that Brush Box will give you that cohesive resort look.

Visualizing the Result

Before you start digging curves into your lawn or buying 50 pots of Xanadu, you need to verify the spacing. A sketch is great, but it doesn't show you shadows or volume. Using GardenDream acts as a safety net here. You can upload your site photo and overlay the curved bed lines to see if they actually break the "bowling alley" effect or if they just look messy.

It also helps you verify that your new shade tree is actually positioned to block the sun where you need it, rather than shading the neighbor's roof. If you want to spot hidden opportunities in your own yard, upload a photo to our Exterior Design App to get an instant diagnosis and visualize the transformation.