Q. Can you tell me what is
killing our rosemary hedge, by inches?
The plant is 15 years old. Other
rosemarys of the same age on the property are still thriving. Any help would be appreciated. Picture attached. Thank you
killing our rosemary hedge, by inches?
The plant is 15 years old. Other
rosemarys of the same age on the property are still thriving. Any help would be appreciated. Picture attached. Thank you
A. There are a few insects
such as spittle bugs that get on rosemary but there are not that many diseases
that affected except some of the soil borne fungal diseases. In other words,
these are disease organisms that are already present in the soil but they need
opportunity in order to take advantage of rosemary. When soils remain wet, this
stresses rosemary and makes it susceptible to these types of diseases. The
usual advantage these diseases get is because soils are from plant stress
because soils are kept too wet from frequent irrigations or the soils do not
drain water fast enough before the next irrigation.
such as spittle bugs that get on rosemary but there are not that many diseases
that affected except some of the soil borne fungal diseases. In other words,
these are disease organisms that are already present in the soil but they need
opportunity in order to take advantage of rosemary. When soils remain wet, this
stresses rosemary and makes it susceptible to these types of diseases. The
usual advantage these diseases get is because soils are from plant stress
because soils are kept too wet from frequent irrigations or the soils do not
drain water fast enough before the next irrigation.
 |
| Rosemary dying is usually a soil or irrigation and drainage problem. |
These diseases attack the
roots of the plant and cause dieback of the top similar to what appears to be
drought. It appears to be drought because the roots are dying and they can no
longer take up water to the tops so, in fact, it is drought but drought caused
by too much water present around the roots.
roots of the plant and cause dieback of the top similar to what appears to be
drought. It appears to be drought because the roots are dying and they can no
longer take up water to the tops so, in fact, it is drought but drought caused
by too much water present around the roots.
Like many Mediterranean
plants, rosemary does not like wet soils in the summertime. They can tolerate
wet soils as long as there is drainage and the soil has enough time to dry out
between irrigations. These types of diseases frequently start at low spots in
the irrigated area where water collects or puddles. Usually plants growing
where the water has drained to low spots remain healthy.
plants, rosemary does not like wet soils in the summertime. They can tolerate
wet soils as long as there is drainage and the soil has enough time to dry out
between irrigations. These types of diseases frequently start at low spots in
the irrigated area where water collects or puddles. Usually plants growing
where the water has drained to low spots remain healthy.
Plants that have extensive
root rot from soil disease organisms frequently will pull from the soil fairly
easily or are loose in the soil when they are pulled from side to side.
root rot from soil disease organisms frequently will pull from the soil fairly
easily or are loose in the soil when they are pulled from side to side.
The solution? The usual
solutions are to water less often or improve the drainage in the soils or both.
Rock mulches around rosemary will cause the soil to become more compacted and
not drain water well. Organic wood chip mulches help to keep the soil
“fluffy” and improve drainage. Organic wood chip mulches help to keep
soils more moist so the frequency of irrigation typically has to be less.
If
this problem was caused from soil disease organisms it will be difficult to
reap plant rosemary in that soil again. You might have to remove the soil from
that spot and replace it with an amended soil before you replant another
rosemary in that same location.
solutions are to water less often or improve the drainage in the soils or both.
Rock mulches around rosemary will cause the soil to become more compacted and
not drain water well. Organic wood chip mulches help to keep the soil
“fluffy” and improve drainage. Organic wood chip mulches help to keep
soils more moist so the frequency of irrigation typically has to be less.
If
this problem was caused from soil disease organisms it will be difficult to
reap plant rosemary in that soil again. You might have to remove the soil from
that spot and replace it with an amended soil before you replant another
rosemary in that same location.