How to Make a Pinecone Open

Pinecones respond to changes in humidity levels.

Pinecones -- the female seed-dispersing organ of pine trees -- can open or close depending on humidity levels. Because dry conditions are more advantageous for seed germination than wet conditions, the scales of pinecones open to release their seeds when the air is dry. By waiting until the right time to open, pinecones give the seeds an extra advantage that helps them survive in difficult conditions. Craft enthusiasts can use an oven at home to replicate these environmental cues and cause their pinecones to open.

Things You'll Need

• Baking sheet
• Aluminum foil

Instructions

1. Preheat oven to 200 degrees Fahrenheit.

2. Line a baking sheet with aluminum foil to prevent the pinecone's sap from sticking to the sheet.

3. Place your pinecones on the baking sheet in one layer. Allow an inch or two of space between the cones.

4. Place the baking sheet with the pinecones into the oven for about 20 to 30 minutes, or until the cones have opened and are shiny with sap.

5. Remove the baking sheet from the oven and allow the pinecones to cool completely before handling.

Tips & Warnings

• Opened pinecones may close again if placed in a humid or wet environment. If this happens, repeat the above steps.

• Do not heat the pinecones at a temperature greater than 225 degrees Fahrenheit. Increasing the temperature could create a fire hazard.

References

• Make-Stuff: Things You Can Do With Pine Cones
• TipNut: How To Prepare & Preserve Pine Cones
• North County Times: Q & A - Why do pine cones open and close?
• Exotic Bird: Pinecones