Friday, January 26, 2007

NYC Roof Gardens in Winter

Winter Gardens

NYC: Unbelievable cold today (9 degrees with face numbing windchill). Tomorrow the forecast is 40 and warmer on Sunday. It's been an incredibly mild winter in most of the Northeast (except for today) -- but not much rain since winter began.
In times of mild weather and little rain, containers can dry out. Last February and March, for instance, the temperatures were mild but only a few inches of rain. We lost two large Cryptomeria trees (See photo above; tree on left/center is the Cryptomeria) -- not because of severe cold -- the reason usually cited for Cryptomeria death -- but because of lack of water in late winter/early spring. Since irrigation systems are not turned on until all danger of frost is over, most container gardens -- and even some inground ones -- may require hand watering when temperatures are mild and there isn't much precipitation. When it's supposed to be winter ... frozen; dormant ... but it's not really.

Use the "finger test" to determine if you do need to water. If the surface soil to 2" is dry, water deeply, until the water runs out of the bottom of the container. Avoid sprinkling or spraying the soil. Roots gravitate toward water (and oxygen) and if water penetrates to only within a few inches of the surface, you'll have roots growing up -- and not down and out, the way they are supposed to grow. Always water deeply with an open hose (remove the nozzle). To make certain the water is penetrating all part of the container or if the soil is very dry, water once thoroughly and then repeat.

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Great Garden Resources:
Trellis Structures in E. Templeton, MA
Beautifully made arbors, pergolas, and trellises at reasonable prices.
They ship most items, but will deliver to the city on larger and custom

Bottega Furniture in Dayton, OH
Handmade outdoor furniture made of Ipe; unusual design, elegant,
but sturdy. Met thm at the NYC Home&Garden show a few years
ago. Wonderful stuff.

1 comment:

Unknown said...

Yes. I've found that it is so easy, in seasons when the weather is mild, to tell the moisture content of the soil by the appearance of the plant. But in the winter, cold and barren, it is quite hard to discern the prevailing conditions in the pots, and the plants, turned in on themselves, offer very little indication of their environment. So, in future, I'll let my fingers be an instrument for proxy for the plants, and divine if water is needed. Thank you for the suggestion.