Hydrangeas - to feed or not to feed?

Discussion in 'Outdoor Gardening in the Pacific Northwest' started by Glenn M, Mar 24, 2020.

  1. Glenn M

    Glenn M New Member

    Messages:
    4
    Likes Received:
    0
    Location:
    USA, California
    We have a small garden with pre-existed hydrangeas (left from previous owner) - unfortunately, I have no idea what variety they are. All I can say it's 5 feet tall, and last year there was no blooming, so this year I decided to give them a boost. Pruned the old branches last autumn according to guidelines and considering feeding them.
    So I have a question - which fertilizer do you use for hydrangeas? And why?
    Also when it's better to apply (through the season or at spring + late autumn only)?
     
    Last edited: Mar 29, 2020
  2. Andrew Matheson

    Andrew Matheson Member UBC Botanical Garden

    Messages:
    45
    Likes Received:
    8
    Location:
    Vancouver, BC
    Hi there,

    In terms of pruning the plant, it would be helpful to at the very least know the growth habit of the plant. Is it sending up several shoots from the ground? Or is it branching, with just one or two trunks coming from the ground?

    It is a general tenet of my own garden philosophy that I do as little soil amending as possible, depending on what the needs are of a garden space. I have also heard that an overfeeding of nitrogen (such as from a lawn) could actually prevent hydrangeas from flowering (thought I need to fact check this). Whether or not your plant is lacking in nutrients won't only affect the flowers but it would also affect the vegetation- how healthy were the leaves last year? If they were perfectly healthy, I think it is doubtful that the plants need to be fertilized.

    I have two suspicions as to why they aren't flowering. One is sunlight- if they are receiving too little sun, they won't flower. Since you are in California, I would guess (depending on where you live) that you have abundance of sunlight, so morning sun and afternoon shade would be ideal. If they are in deep shade, it is possible they won't flower. The second is that the wood is quite old, and pruning (in fall, as you said) is necessary for rejuvenation. I personally would wait and see what affect your pruning has had before adding fertilizers, and consider if it is getting adequate sunlight.
     
    Daniel Mosquin likes this.

Share This Page