Be Careful How Juniper is Trimmed!

Q. My junipers are starting to die and turn yellow from the top. I water them twice a day; at 7:00am and 7:00 pm for 45:00 minutes. The nursery told me to water them every other day, 4 days a week, for 1 hour.What should I do to save them?

Junipers are not desert plants and may not fare very well over time when surrounded by rock mulch

A. I saw the pictures you sent. They appear to be sheared as well. Because of dense, internal shading due to their thick canopies, the "leaves" inside the canopy of these plants die and turn brown. It is only the outer perimeter of leaves that stay green. The inside stems aren't dead but the "leaves" or "needles" attached to them die and turn brown from a lack of light.

            When these plants are sheared, the dead, brown needles in the interior are revealed. Some junipers "re-sprout" from these brown, seemingly dead stems but others may not. However, new growth is slow when they “resprout”.

            Spider mites can also cause needles to brown and drop off. Don't assume your plant has spider mites unless you confirm their presence.

            I use a white piece of paper and "slap" a brown branches against the white piece of paper several times. This dislodges the spider mites from the needles onto the white piece of paper. By staring at the white piece of paper for 10 or 15 seconds, you can these tiny spider mites crawling around on it. You must look closely because they are the size of the period at the end of this sentence.

            Washing plants prone to spider mites once a month with a stiff stream of water removes surface dust from the needles or leaves. Removing the dust and dirt also helps control spider mite populations. Soap and water sprays also work if spider mite outbreaks are light.

            Junipers are notorious for dying if the soil is kept too wet. Their roots suffocate easily in wet soils. The first sign of overwatering is browning of the tips of the stems. This can be from soils that don't drain easily or when these soils are irrigated too often.

            Be careful of that. Juniper roots like to be on the dry side between irrigations. I think this is what the nursery was hinting at.

            It’s hard to judge how many minutes to give them but each of them should be fine if they receive 5 gallons of water each, distributed under their canopies. This would require at least 2 drip emitters but 3 would be better.