the truth about moisture, mould, and resin preservation

When you receive a stunning bouquet, whether for your wedding, a milestone birthday, or a sentimental occasion, it is natural to wish those flowers could last forever. But if left in a vase, nature eventually takes its course, and flowers begin to rot, wilt, and decay.

When people ask, "do flowers rot?" the answer depends entirely on how they are handled. If left untreated or processed incorrectly, yes, flowers will rot. However, when preserved properly, flowers will not rot, holding their beauty for years to come.

Understanding why flowers rot, and how to prevent it, comes down to one single, critical factor: moisture.

 

Why Fresh Flowers Rot in Resin

It can be tempting to think that pouring clear, liquid resin over a fresh, vibrant flower will freeze it in time like ice. Unfortunately, doing this leads to total preservation failure.

Fresh flowers are packed with natural moisture. If fresh flowers are cast directly into resin:

Trapped Moisture: The resin seals the flower, trapping liquid inside with nowhere to evaporate.

Mould & Decay: The organic material begins to decompose, creating mould and rot inside the resin.

Cloudiness & Ruined Castings: As the trapped moisture reacts with the resin, it releases gases, causing the clear resin block to turn cloudy, brown, or discoloured from the inside out.

 

Drying: The Most Critical Step in Preservation

Drying is the foundation of successful flower preservation, it is the single point where the process either succeeds or goes wrong. Flowers must be 100% fully dried before they ever touch a single drop of resin.

When flowers are dried correctly using professional techniques (such as submersing them in specialised silica sand or using controlled drying environments):

All moisture is removed: Without water, bacteria and mould cannot survive, completely stopping the decay process.

Structure is locked in: Dehydrating the flowers stabilises their shape, allowing them to withstand the weight of the liquid resin without collapsing or shrivelling.

Colour is locked in: While colours shift slightly during dehydration (whites soften to ivory, deep reds darken), properly dried flowers hold their dried hue permanently once sealed inside resin.

 

Correctly Dried Flowers Do Not Rot

Once all moisture has been removed, the dried flowers are carefully encased in crystal-clear resin. Because there is zero moisture left inside, the flowers will never rot, decay, or go mouldy inside their resin block.

At Rachel Makes Resin, drying is treated as a precise, unhurried science. Taking the extra time to ensure every flower is thoroughly dried is what guarantees your sentimental keepsake remains clear, vibrant, and beautiful for a lifetime.