Pineapple Crown Regrowth in Soil, Sand, and Water
Medium
You have probably thrown away a pineapple top without thinking twice. But that leafy crown can regrow into a new plant. The question is which growing medium works best.
You place sixteen pineapple crowns into four groups. One group goes into potting soil. One goes into sand. One goes into water. One goes into soil with added fertilizer. You measure root growth each week.
The results are surprising. The crowns in plain water grow roots faster than all other groups. Soil and fertilizer do not speed things up.
Hypothesis
The hypothesis is that the pineapple will grow faster and be healthier in rich soil than in water or sand.
Science Concepts Learned
Growing Media
Not all growing media are equal when it comes to rooting speed. Sixteen pineapple crowns are split into four groups — potting soil, sand, plain water, and soil with added fertilizer — and root growth is measured each week. The results challenge the obvious assumption: the crowns in plain water root faster than any other group. Soil and fertilizer do not speed things up. A simpler medium, it turns out, can outperform richer ones.
Method & Materials
You will need to gather materials such as pineapple crowns, soil, water, fertilizer, 16 pots, and sand. Then you will put 1 crown into each pot 6 cm deep in the soil. Finally, you will water the plant groups every 3 days and take observations every week.
You will need 16 4" plastic pots, 16 pineapple crowns, 1034 grams potting soil, 1040 grams sand, 129 grams fertilizer, 1 250ml measuring cup, 20ml planting food, 15cm ruler, and hard water.
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See what’s includedResults
The results of this experiment showed that the pineapple grew more effectively in water than in potting soil, or in sand or soil containing fertilizer. This suggests that water is the best environment for growing pineapples. An interesting observation was that the pineapple roots grew much faster in water than in rich soil or sand.
Why do this project?
This science project is interesting because it shows that water is the best environment for growing pineapples, which is contrary to what many people may think.
Also Consider
Variations to consider include growing the pineapples in a greenhouse to keep the soil moist, and growing them at a higher temperature.
Full project details
Additional information and source material for this project are available below.Related video
These videos explain the science behind this project and demonstrate key concepts used in the experiment.
It's amazing to think that something we usually throw away, like the top of a pineapple, can actually be used to grow a whole new pineapple! Waiting two years for the fruit to grow might seem like a long time, but it's definitely worth it for the satisfaction of growing your own fruit! According to this experienced gardener, planting the pineapple top in soil is the way to go, as it helps the roots adjust better when transplanted and leads to a healthier plant.
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