Not crazy but operating under the belief of a very old but unsubstantiated gardening myth :-)

It was believed that putting pennies in the planting hole of a new hydrangea would influence flower color. Not true :-) It is the availability of aluminum ions in the soil that either create or inhibit the blue color. Since pennies contain no aluminum (nor do any other coins), dumping an entire piggy bank into the hole would have no effect! Same thing with the rusty nails or rusty cans alternative scenarios - long held but no scientific basis gardening myths.

Here is part of an excellent post written by my friend Al discussing this same subject on another forum several years ago: "Actually it is plant cellular pH that determines bloom color, not soil pH. Lowering soil pH makes aluminum ions readily available for plant uptake where it bonds to pigments in the blooms.

Three different pigments - chlorophyll, flavonoids, and carotenoids - mixed in different proportions, give color to plants. By mixing and matching the three pigments, an endless variety of colors can be created. E.g. most reds are the result of mixing orange carotenoids with magenta flavonoids. Cellular pH (not to be confused with soil pH) has a profound effect on plant color.

Even most experienced gardeners think that lowering soil pH produces blue blooms in hydrangea. Technically, it is only a part of the equation. Lowering soil pH makes aluminum ions more readily available for plant uptake. The aluminum is then available to bond with pigment compounds (anthocyanin, the colored component of flavonoids) changing the way color is reflected. Our perception is blooms changing from pink to blue."

Cellular pH (not to be confused with soil pH) has a profound effect on plant color. I want to emphasize this point - this explains why some hydrangeas are very reluctant to change colors regardless of how acidic the soil is or how available the aluminum is. They are just not genetically programmed to do so.

Grandmas system of gardening may not pass the test when looked at from a scientific perspective, but once you have signed on to grannies method, it is hard to give up. To this day I can not bring myself to plant a Daphne without burying a few rusty nails in the soil. I just can't risk losing a good plant. Al

Thank you guys glad she wasn't crazy just old fashon!!! I think to honor her I will put some pennies in their holes.

I put horse shoes in the planting hole's of blue hyd when I plant them. I put four or five around the base of the plant.