In this post I’m talking about what should or could go underneath your pumpkin. Something new growers might not think about. At the end I also have the latest video I put together talking about my plants getting eaten, and a problem with my watering setup.

Why would you want to put something underneath your giant pumpkin?

The short answer is to help it. Help it grow more easily, help protect it and help it grow with a flat bottom.

What Items Can You Grow Your Giant Pumpkin On?

It’s interesting reading some of the old giant pumpkin growing books out there. At one point in time polystyrene seemed to be the go to thing to have your pumpkin grow on.

Over time this has fallen out of fashion.

One of the main reasons to have your pumpkin grow on something is to help it grow. To provide as less friction as possible when it is packing on the weight.

Growing Directly on Dirt

Growing directly onto the soil in your patch or area you are growing is the usual thing for new growers.

It makes sense to do this. Pumpkins grow on the ground all the time.

Sure.

But we aren’t talking about normal pumpkins here, we are talking about giants.

Pumpkins that can weigh over 800kg.

Your pumpkins might not get to that weight this growing season. But it is achievable to get to get over 100, 200, 300kg.

With all of that weight pushing down into the soil, it can make it hard for the pumpkin to expand and grow.

And sometimes your pumpkin will weigh light compared to the weight estimation charts.

I’ve experienced this before. Growing straight onto the soil can sometimes result in the pumpkin having a concave bottom. The goal here is to have a nice flat bottom to your pumpkin.

More pumpkin = more weight.

Sand is Your Giant Pumpkins Friend

Having a bed of sand underneath your pumpkin allows it to grow more easily. It makes sense, think about how easy it is to have sand flow through your fingers.

Close Up of Blossom End of Pumpkin Growing on Sand

It’s made up of many small particles. Allowing less friction than if you were growing directly on soil. It allows water to pass through it and is dries quickly.

Get Washed Sand

While we do have easy access to many beaches around NZ. I’d suggest getting some washed sand. You can pick this up at all the usual places like Bunnings or Mitre 10.

It will be clean, free from random pieces of shell etc and won’t smell.

You will probably need more than you think.

Laying that bed of sand underneath the pumpkin when it is still manageable is the key. Making sure you put enough down at this early stage will reduce potential headaches later on.

What Goes Underneath the Sand

Remember how I mentioned the weight of the pumpkin and the magic of gravity and pull the pumpkin into the patch?

This is where something underneath the sand comes into play.

For some growers this will be a sheet of plywood.

On face value this makes sense. It is sturdy and will deal with the weight of the pumpkin. And a lot of growers will use this.

But I have 2 concerns around this if that is the right word to use.

  • Plywood can be expensive. Just having it lying around under a pumpkin seems crazy to me.
  • It’s completely solid – Water can’t pass through it. What happens if water somehow pools at the base or underneath the pumpkin?

These are just the points that spring to mind. But top growers use this method with no real problems it seems.

Along Came Mill Fabric

I’m not sure what the origin story is of how this started to be used by giant pumpkin growers. But for a few years now growers in the US use this red/orange looking material under their pumpkins.

They call it Mill Fabric.

Mill Fabric Close Up

Pumpkin Growing on Mill Fabric

It took a while to figure out what it actually is. Turns out it is used in pulp and paper mills.

It’s used when they squish the water out of the wood pulp and after so many days it gets partially clogged with wood fibre and they need to use new pieces of it.

Made from woven pieces of what looks like plastic. This material is super strong, flexible and allows water to pass through it.

This product combined with the sand seems like a good combo. As the pumpkin grows it can easily push the sand when needed along the mill fabric.

You Might Need to Move Your Pumpkin

One thing you might not be aware of or have encountered yet is the need to move your pumpkin.

When your pumpkin is first pollinated on the vine, one of things you need to make sure is that there is enough slack in your vine.

Giant Pumpkin Growing on Mill Fabric with Vines Showing

When your pumpkin grows, it gets taller. All that height, and growth of the pumpkin can put a massive strain on the vine. Especially where it is connected to the pumpkin.

The last thing you want is the pumpkin breaking this connection from the vine. If that happens, no more growth and your season has ended.

Having it on something more solid than soil combine with the bed of sand allows you to move your pumpkin if you need to. This may sound hard to do, and it can be when the pumpkins are getting super heavy.

Giant Pumpkin Growing on Sand on Top of Mill Fabric

Straps, a ratchet or chain block and you can moved your pumpkin the couple of centimeters it needs. The sand allow the pumpkin to slide easily.

Where to Get Mill Fabric From?

I managed to track some down. I’ve taken the massive rolls and worked out the best way to cut this material. It’s a time consuming process.

I’ve got limited stock of mill fabric on the store right now. Check it out here.

Mill Fabric on the Ground

The store says it’s out of stock. But if your keen on some please email me. You can pick it up from me in Hamilton.

Or I can get it couriered to you.

To save confusion, and to make sure you pay cheapest shipping cost as it is a bulky item, I need to work this out. Hence why it says it is out of stock.

So there we go. There’s some options for what to put underneath your pumpkin.

I wonder if in the future there will a new better item growers will want to be use.