Irrigation Do’s and Don’t’s

As a general rule:

  • YEAR ONE: 15 minutes a day, every day, from the months of April through Oct.
  • YEAR TWO: 30 minutes, 3 times a week from April through Oct. Soaker hoses and drip emitters should also be moved further from the trunk in the second year.
  • YEAR THREE and Beyond: water only during the hottest part of the year. In the Pacific Northwest, that’s usually June, July, August and lately, September.


  • Use a timer – it is required for our warranty. It takes the worry out of irrigation and assures that your trees get the same amount of water every day. (NOTE: Our warranty only applies to trees purchased from and planted by Big Trees.)
  • Water every day. It’s critical for new trees to establish their fine root structure.
  • Make sure your emitters or soaker hose are actually over the root ball. Watering outside the root ball will not benefit your tree the first year. Typically this is within 6 inches of the trunk. When using a soaker hose, use 1 to 2 rings depending on the size of your rootball. One ring 6” out from the trunk, and one closer to the outer edge of the rootball.
  • Check system weekly to see if it’s still functional, especially during our summer months.
    • – 1 inch per tree caliper = 1 gallon per inch daily. So a 2 inch tree should get 2 gallons of water per day.
    • – Calibrate your system to know how much water it’s putting out. Place your soaker hose or drip emitter into a 1 gallon bucket and time how long it takes to fill the bucket. Remember, if you are watering multiple trees on the same line, you will have to multiply the number of trees.
  • Put away your timer for the winter. Replace the batteries when you set it back up in the spring.


  • Don’t overwater. Yes, you can actually overwater your new tree. Overwatering is one of the biggest reasons we see new trees die. Dig 6-8” down and if you can grab a handful of soil and wring water out of it, you are overwatering.
  • Don’t rely on rain. Many trees have thick canopies and rainwater typically does not make it through to the top of the root balls.
  • Avoid runoff. Trees planted on slopes can be tricky to water without your irrigation ending up at the bottom of your hill. Build a basin to keep the water from escaping.
  • Avoid spraying water on the leaves and trunk. This can lead to fungal diseases.
  • Don’t water while there is still threat of freezing temperatures. (Typically November-March.)

If you have any questions or concerns with your new tree or irrigation set up, please contact us. We are happy to answer any questions you have.