How Do I Choose the Right Kenzan Size for My Vase?

Quick answer: choose a kenzan that fits comfortably on the flat inside floor of your vessel and provides enough stability for the flowers or branches you want to arrange.

Do not choose by vase diameter alone. A wide bowl can have a small flat base, while tall or heavy plant material may need a heavier kenzan even when the vessel itself is not especially large.

For weighted SUWADA kenzan, the current choices are 61 mm / 250 g, 80 mm / 490 g and 90 mm / 620 g.

Start by measuring the inside bottom of the vase

The first measurement that matters is not the widest part of the vase.

Measure the usable flat area inside the bottom where the kenzan will actually sit.

A bowl may be 20 cm wide at the rim but curve sharply toward the bottom. In that case, a 90 mm kenzan might not sit flat even though it seems small compared with the overall vessel.

Before choosing a size, check:

• the diameter or width of the flat interior floor;
• whether the bottom is level;
• whether the kenzan can sit fully supported;
• whether enough room remains around it for the composition you want.

A kenzan should not be wedged against the sides of the vessel simply because it technically fits.

Kenzan diameter and kenzan weight are not the same thing

Diameter tells you whether the holder physically fits.

Weight helps determine how much stability it can provide.

This distinction becomes important with tall flowers, branches or arrangements that extend far away from the centre of the kenzan.

A stem leaning strongly to one side creates more leverage than a short upright flower.

That means two arrangements using the same number of stems may need very different levels of support.

When choosing a kenzan, think about:

vessel floor → plant material → height and leverage → required stability

rather than simply:

large vase → large kenzan

Which HANAKATSU kenzan size should I choose?

The current weighted HANAKATSU range is:

All three use brass pins set into a weighted lead base with a soft elastomer underside.

The difference is therefore not simply the number of pins. Moving from 61 to 80 or 90 mm also gives you substantially more base weight.

When is the 61 mm kenzan enough?

The 61 mm HANAKATSU is a good starting point when:

• the vessel has a relatively compact floor;
• the arrangement uses flowers or lighter foliage;
• stems are not exceptionally tall or top-heavy;
• the composition stays reasonably close to the centre of the holder;
• you want the kenzan to occupy less visual and physical space in the vessel.

At 250 g, it is still a weighted kenzan rather than a miniature holder.

For many simple home arrangements, that can be enough.

But “small” does not mean that it is automatically the correct choice for every small vase. A narrow vessel containing one tall, stiff branch may create more leverage than a wider arrangement of soft flowers.

When should I choose the 80 mm kenzan?

The 80 mm HANAKATSU increases the base weight to 490 g.

That makes it useful when you need more stability for:

• taller stems;
• more plant material;
• heavier flower heads;
• stronger angles;
• medium or larger shallow vessels;
• arrangements where the centre of gravity sits farther from the kenzan.

For someone buying one traditional weighted kenzan for a range of general flower arrangements, 80 mm offers more support than the 61 mm without taking up as much vessel space as the 90 mm.

That does not make it universally “the best size.” It simply occupies a useful middle position in the current range.

When does the 90 mm kenzan make sense?

The 90 mm Extra Large HANAKATSU weighs approximately 620 g.

It makes sense when:

• the vessel has enough flat floor area to accept it;
• you are using taller or heavier plant material;
• branches create substantial sideways leverage;
• the arrangement requires more stability than the smaller bases provide;
• the kenzan itself will not visually overwhelm the available space.

Bigger is not automatically better.

A 90 mm holder in a small bowl may leave too little open water or visual space around the arrangement.

The purpose of choosing a larger kenzan is support, not simply filling the vessel.

Can a kenzan be too large for a vase?

Yes.

There are two ways this can happen.

It may be physically too large

If the bottom of the vessel curves upward before the edge of the kenzan, the holder cannot sit properly.

A kenzan needs stable contact with the vessel floor.

It may be visually too large

Even when it fits physically, a large kenzan can occupy too much of a small or open composition.

In ikebana and other deliberately sparse arrangements, empty space is part of the design.

A holder that dominates the bottom of the vessel may work mechanically while feeling disproportionate visually.

Can I use a small kenzan in a large bowl?

Yes.

A large bowl does not automatically require a large kenzan.

If the arrangement uses only a few relatively light stems, a smaller weighted holder may work perfectly well.

The vessel and the arrangement should be considered separately.

For example:

• a wide bowl with three short flowers may need relatively little support;
• a narrower bowl holding a tall branch at a strong angle may need much more.

The size of the vessel tells you what can physically fit.

The plant material tells you how much stability you actually need.

What if my vase is very small?

For tiny vessels, single stems or very small compositions, a full-size weighted kenzan may simply take up too much room.

The HANAKATSU Mini Kenzan Set contains four separate holders:

• round: Ø23 × H17 mm, 32 g each;
• square: 24 × 24 × H17 mm, 45 g each.

These can be used for a single flower or as several separate support points inside a larger vessel.

Using several small kenzan can also create a different composition from using one large central holder, because the stems do not all have to originate from the same point.

See the HANAKATSU Mini Kenzan Set.

What about AIRIN?

AIRIN should not be compared with a weighted kenzan by diameter alone.

The current sizes are:

AIRIN uses a polycarbonate body and pins with a PVC suction cup underneath.

Its stability therefore comes from attachment to a suitable vessel surface, not from a heavy base.

An AIRIN Large at 78 mm is consequently not the equivalent of an 80 mm HANAKATSU weighing 490 g.

Choose AIRIN when:

• a lightweight holder is useful;
• the vessel surface allows the suction cup to attach securely;
• the arrangement suits that attachment method.

Always check that the suction cup is secure before adding plant material.

See the AIRIN Lightweight Kenzan.

Does the kenzan need to fill the vase?

No.

A kenzan only needs to provide enough pin area and stability for the arrangement while fitting safely inside the vessel.

There is no universal rule that says the kenzan must occupy a fixed percentage of the vase diameter.

A useful amount of open space around the holder may actually be desirable, particularly in a shallow vessel where water and negative space remain visible parts of the composition.

Should I choose the size based on flower height?

Height matters, but not by itself.

Tall material creates more leverage, especially when it leans away from the centre.

But also consider:

• how heavy the flowers or branches are;
• whether they are soft or woody;
• how far they extend sideways;
• how many stems are concentrated on one side;
• how stiff the material is;
• how much counterweight the base provides.

A tall, light grass stem and a short, dense branch are very different mechanical problems even if one is physically taller.

What if I am using thick branches?

A larger kenzan can provide more weight and a larger pin field, but the stem still needs to be prepared correctly and positioned safely on the pins.

Do not assume that simply choosing the largest holder makes every branch appropriate.

The arrangement must remain stable as a whole.

If a branch repeatedly pulls the holder upward, twists it or makes the vessel unstable, reconsider the support, stem position or arrangement rather than forcing it.

A simple starting guide

Use this as a starting point rather than a strict formula:

The final decision still depends on the actual vessel and plant material.

So, what size kenzan do I need?

Choose in this order:

1. Measure the flat inside floor of the vessel.

The kenzan must sit fully and safely on that surface.

2. Look at the plant material.

More weight, height or sideways leverage generally demands greater stability.

3. Decide whether you want weight or suction attachment.

HANAKATSU relies primarily on a weighted base. AIRIN uses a suction cup.

4. Choose the smallest size that provides the support your arrangement actually needs.

There is no advantage in filling the vessel with more kenzan than necessary.

For the current SUWADA range:

• 61 mm / 250 g — compact weighted arrangements;
• 80 mm / 490 g — more support for general arrangements;
• 90 mm / 620 g — larger or heavier arrangements where the vessel can accommodate it;
• Mini — single stems, tiny vessels or separate support points;
• AIRIN 53 / 78 mm — lightweight suction-mounted alternatives.

If you are new to the tool itself, start with What Is a Kenzan?.

If you are deciding between a pin holder and another flower-arranging mechanic, read Kenzan vs Floral Foam: What Is the Difference?.

You can also compare all current options in our Japanese Kenzan & Ikebana collection.