Some of the aucuba have leaves that are turning black and wilting. … They are
suffering from Phytophthora root rot
, a soil disease that commonly affects azalea, rhododendron and aucuba shrubs. The fungus itself is present in most soils.
Why has my aucuba gone black?
The blackening of the leaves is usually
caused by root stress due to excess moisture levels in the soil during cold, wet winters
. Other forms of stress, including root diseases (mainly phytophthora root rots) might also be involved.
Why is my aucuba losing leaves?
Aucuba needs an organic, acid soil that is evenly moist yet well drained meaning damp like a wrung out sponge and not saturated/sopping wet or dried out.
Yellowing and dropping foliage
can be a sign of overwatering or poorly drained soil, especially if it happens near the bottom of the plant first.
Why is my spotted laurel dying?
This type of damage often occurs on spotted laurel (Aucuba japonica), with complete sections of the plant suddenly turning black and dying off. The most common cause is
a soil-borne disease possibly Phytophthora root rot
.
Does aucuba grow in full sun?
Winter hardy to USDA Zones 7-9 where this shrub is best grown in moist, organically rich, well-drained soils in
part shade to full shade
. Plants need significant amounts of shade in hot summer climates (young leaves will often burn in full sun).
What causes Phytophthora rot?
Phytophthora root and stem rot is a soil-borne fungal disease caused by
Phytophthora sojae
. This pathogen causes seed rots, pre- and post emergence damping off of seedlings and stem rot of plants at various growth stages. Disease development is favored by soil temperatures is above 60oF and high soil moisture.
How do you care for aucuba?
Clean up plants as necessary by
snipping off broken, dead, and diseased foliage and twigs
. Aucuba shrubs have moderate drought tolerance, but they grow best in moist soil. Water often enough to keep the soil moderately moist using cold water. Hot water from a hose that has been left in the sun can encourage disease.
How do you prune aucuba?
Pruning is simply a matter of cutting the shrub back to shape and size.
Prune the stems and avoid cutting the leaves
. If you cut the leaves they will discolour at the edges although they grow through this after a year.
How do you take cuttings from aucuba?
- Fill small pots with a rooting medium that drains freely. …
- Remove the leaves from the lower half of the stem and cut the remaining leaves in half. …
- Stick the lower half of the cutting into the soil.
How much water does a Japanese aucuba need weekly?
The aucuba japonica is easy to water. The soil should always remain a bit moist and during the growing season, make sure to water the plant
once weekly
. In hotter climates, you can water the plant twice a week or every three days to prevent the soil from getting dried out.
Will spotted laurel grow in shade?
A versatile evergreen shrub for almost anywhere in the garden. Slow-growing, it will only reach 1.8m (6ft) after ten years if left unpruned. Like all aucuba varieties, ‘Crotonifolia’
will grow in both full sun and shade
– although its gold-blotched and finely-speckled leaves colour best in partial shade.
How do I encourage laurel growth?
Use a Fertiliser
Using fertiliser
is a great way to encourage laurel growth. Established laurels grow better with the help of balanced fertilisers such as Rootgrow fertiliser, whereas new laurels struggling to establish and grow prefer a natural, organic fertiliser such as Bonemeal.
How is Phytophthora treated?
Hydrogen Peroxide
— The application of a 3% solution of household hydrogen peroxide to your soil is effective in killing pathogens and diseases like Phytophthora. Apply a mixture of 1 part peroxide to 3 parts water and allow it to penetrate the soil before regular watering resumes.
How often do you water aucuba?
However, houseplants should be consistently watered when the top layer of soil dries to a depth of approximately two inches. Established shrubs will only need to be watered
once every few weeks
, and more often in drought-like conditions.
What looks good with aucuba?
In the tropical-style garden, group aucubas boldly with
fatsias, hostas or plantain lilies
. In both the tropical and woodland settings, use the variegated forms with blue hydrangeas. The combination is a little gaudy but very colorful. Bedding plants also work quite well as companions.
Will aucuba grow under trees?
Aucuba is hardy in USDA zones 7 to 10. It prefers partial to full shade and well-drained, moist, highly organic soil.
Underneath deciduous trees is not a good place
as the plant needs shade in the winter as well as in the summer. Leaves exposed to sun will turn black.
