Question
Hi. I'm in the process of building a grape trellis/arbor.  I bought two 4x4 eight-foot posts.  My question is how deep should these posts be in the ground.  I live in central California.  The posts will be inserted into 6x8 concrete blocks. Thank you for your help.

Answer
They need to be 24 inches deep to support the future weight of mature vines and set in concrete not blocks. Best of luck/


Sean J Murphy, RLA, ISA, LEED AP

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http://www.seanjmurphy.com
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