When a succulent
isn't looking quite right
You may wonder if
you've done something wrong.
I'm Debra Lee Baldwin
with my Rogue's Gallery
of common pests and problems,
symptoms, causes, severity,
prevention and treatments.
Abrasion is unsightly.
Plants eventually outgrow it
Aeoniums are especially
prone to brown marks
from being handled.
Lines and blotches
show up a day after
something or someone
has touched the leaves.
If you're making a bouquet
of aeoniums or taking cuttings
hold them by their stems only
and don't let them brush up
against anything.
Agave edema results from
inconsistent watering
it's not serious but it is
unsightly.
Blisters form on
leaves and the skin
sloughs away.
There's
no reversing the damage.
Check to make sure
large agaves are watered
minimally and infrequently.
Agave snout weevil
is fatal, and there's no cure.
If your agave wilts and has
dark patches at leaf axils,
it likely has snout weevil,
a thumbnail sized black
beetle that punctures an
agave's core and inserts
its eggs.
Grubs hatch,
consume the core of the
plant, turn it to mush,
then tunnel into the
ground to pupate.
At the first sign of
infestation, remove the plant
drench the ground below
it and around other agaves
in your garden with a
systemic insecticide.
Plant new agaves bare
root only.
Bare root, this is what
bare root looks like.
Aloe mite is serious
because it spreads.
And there's no known cure.
A microscopic mite
causes bubbly, tumorlike
growth along leaf margins
and flower spikes, and
where leaves meet the stem.
Once the mite is in a
plant's tissues
it'll continue to cause
cancerous growth.
Cut out any affected
tissue and bag it for
the trash.
Sterilize
the tools you use with
bleach or Isopropyl
alcohol.
Aloe mite is
still going to show up
on that particular
plant.
Don't give friends
cuttings from an
infested aloe.
Ant infestation is serious.
Ants nest in the soil
beneath aloes, haworthias,
and gasterias in late summer
and fall, and feed on
the plant's core, which
fills with dirt as the pests
push it up from below.
Peel away damaged
leaves until you have
a clean, unblemished
core, and wash the roots.
Aphids are not serious
but they do cause
distorted growth.
Ants place aphids on
plants in order to feed
on the bugs' sweet,
sticky secretions.
Blast the pests with a
strong spray of water,
release lady bugs and
other beneficial
insects that prey on
the pests,
isolate affected
succulents, and
spray the pests
with Isopropyl alcohol.
Black spots are not
serious, but they are
unsightly, and there's
no known cure.
It's likely a fungus.
It affects aloes, haworthias,
and gasterias.
It will
spread, perhaps due to
moist air.
Keep leaves
dry, locate plants where
there's good air circulation,
and remove affected leaves,
sterilizing your tools
after each cut.
Blotchy leaves usually
are normal.
Leaves of
rosette succulents such
as graptopetalums,
graptoverias, aloes, and
echeverias, change color
according to light conditions.
The more light,
the more rosy the leaves.
When transitioning
from green to red or
vice-versa, leaves may
appear blotchy.
Color change is normal
Nurseries are pros at
producing colorful,
healthy succulents
because they sell better
than plain green ones.
When you bring a red,
orange, yellow, or purple
succulent home, then
don't give it the same
amount of sun, it may
revert to green.
On the
plus side, solid green
succulents do tend to
be more vigorous.
They'll grow larger
more rapidly than their
colorful cousins.
Cochineal scale is
not serious but it's
unsightly.
And it spreads.
It forms dots of white fluff on
paddle cacti and will dye
your fingertips red if you
mash it.
Blast the plant
with hose water to dislodge
the pests.
Spray the pads
with Neem oil in winter,
and release beneficial
predatory insects, such as
ladybugs, in spring.
Dead lower leaves
are normal if the
succulent's center growth
is healthy.
New leaves
form at the center of a
succulent's rosette, or
from the tip of its stem.
Older leaves wither and
die, and may persist
on the stem, thereby
shading it from harsh
sun and insulating it
from cold.
If you find
them unsightly, go ahead
and peel them away.
Another reason to
remove them is that
they may harbor pests,
such as mealy bugs.
Deer can cause serious
damage.
At first sign of
large bites taken out of
leaves, apply a deer
repellent that contains
garlic.
If the situation
becomes intolerable,
your only recourse
may be to surround
your garden with
7-foot fencing.
When formerly plump
leaves become
wrinkled and lose
their sheen, it's a
sign that they're
drying out.
During
times of drought
in their native habitats,
succulents live off the
moisture in their leaves
So they can survive
a lack of water that
would kill other plants.
So long as the succulent's
vital core is healthy
and hasn't been compromised
by pests that prey on
weakened plants,
it will recover when watered
or the rains return.
Mildew on red apple
is serious and there's
no known cure.
This was first seen
during the winter of
2014 in Southern
California, where
entire embankments
covered with red apple
ice plant (Aptenia
cordifolia) withered
and died, leaving a
tangle of dry stems.
Remove them, and
when you replant,
don't install any kind
of ice plant.
The
susceptibility of other
ice plants has yet to
be determined.
Succulents tend to grow
in the direction of greatest
sun exposure.
Leaves
and stems that appear
stretched or leaning
are "etiolated," a term
that means growth that
results from inadequate
light.
Etiolated rosette
succulents will flatten
to expose more of their
surface to the sun.
Provide the plant with
more light, gradually,
lest it sunburn, and
rotate potted succulents
and wreaths for even
light exposure, and to
avoid lopsided growth.
Exposed stems are normal.
As a succulent's oldest
leaves wither, die and
fall off, branches and
stems become bare
over time.
I'm just going to replant
maybe an inch or so
just enough to stick
it into the ground.
Snip the healthy
tip growth and replant
it as cuttings.
If you cut above
healthy leaves, the
stem may branch,
creating a fuller plant.
There's no point in
keeping an ugly,
leafless succulent,
so discard it,
roots and all.
If there are no leaves
on the truncated
stem, new growth
is unlikely,
although there are
exceptions, such as
fancy ruffled echeverias.
Frost damage can
be mild to fatal.
Depending on the
type of succulent,
how low the temperatures
drop---keep in mind
water freezes at 32
degrees Fahrenheit---
and how long the frost
lasts, plants may show
damage only on leaf
tips or collapse into mush.
When moisture in the
cells of a frost tender
plant freezes, it expands
and bursts cell walls.
Crassulas, aeoniums,
euphorbias, and kalanchoes
are among the most
frost tender succulents.
Most aloes, echeverias,
cacti and agaves can go
a few degrees below
freezing, although they
may show tip damage.
In winter, check the
weather report for
your area and cover
susceptible plants with
frost cloth or bed sheets.
Wait until spring to trim
damaged tissue.
Not clippers but scissors,
because the tissue on the
agave is really quite thin.
And you just cut it to the
shape of the leaf, like that.
Gophers are not serious
if caught early.
If an agave, yucca, or cactus
keels over, it may have
lost its roots to a gopher,
a small mammal that lives
underground.
Gophers
may eat up into a plant's
core if the tissue is
soft enough.
If you notice in your
garden a low mound
of fresh soil a foot or
so in diameter
or a hole that has
been plugged from below
with soil, dig down
into the tunnel and
set gopher traps.
Use two per tunnel
one in each direction,
to catch the gopher
coming or going.
Hail is usually not serious.
Pock-marked and pitted
leaves of succulents
often result from impact
damage.
Not surprisingly,
soft leaved and thin-skinned
succulents are especially
susceptible.
Prior to a winter storm
that might bring hail,
move vulnerable potted
plants beneath an
overhang.
Protect
in-ground succulents
with a lightweight
mesh that won't crease
or break the leaves,
and that will let
rain through, such as
a lean-to constructed
of old window screens.
What looks like bits of
white lint in leaf axils
are mealy bugs.
They
won't go away on
their own and will
spread rapidly and infest
other plants.
Isolate the
affected succulents and
spray the pests with
Isopropyl alcohol.
You don't have to dilute it,
unless you're really concerned
that you're going to damage
a plant.
You just spray the
centers of the plants,
making sure you drench
the mealy bugs.
Chewed tips of aloes,
haworthias, and other
rosette succulents are
usually caused by
rabbits.
Move potted
plants where bunnies
can't get them, and
surround in-ground
succulents with fencing
and wire mesh.
Mushy tissue at a
succulent's core results
when its roots sit in
water and rot.
If the plant has collapsed
or its leaves have fallen
off and the core is mushy,
it's not salvageable.
If there's still some healthy
tissue, remove the plant
from its pot or garden bed,
and trim away damaged
stems and leaves
until you have a clean,
unblemished cutting.
Replant in fresh soil
that drains well.
Scale insects
latch onto the plant
and consume its
tissues.
The pests
are protected by
a hard outer coating
that makes them
difficult to get rid of.
It's generally best
to bag the plant
and put it out with the trash.
Thoroughly clean the area
around it, and don't put
another one in that location
for six months.
To prevent scale infestation,
give your indoor plants
good air circulation,
and check them often.
Snail damage is seldom
serious, but it is unsightly.
Snails latch onto leaves
and gnaw on them,
creating thumb-sized
oval holes.
Hand-pick the pests,
and treat the infested
area with a biodegradable
snail bait that's nontoxic
to pets and other animals,
such as Sluggo.
What looks like snail tracks
on cactus pads are
stretch marks.
They appear after winter
rains in early spring
when the plants are growing
rapidly.
They don't go away
and can't be prevented,
but on the plus side,
they indicate that your
cacti are thriving.
Sunburn is seldom fatal,
but it's unsightly.
Succulents that haven't
been in full sun
and that are exposed to
it without time to
acclimate will sunburn.
This shows up as white
or brown patches on
the leaves.
Unless a
secondary condition
sets in, such as rot,
the plants will recover.
Sunburn is common on
newly planted cuttings
that have yet to
develop roots and
whenever bright, hot
sun follows days of dim
light and cloudy skies.
Weak growth is usually preventable.
Thin, pale and spindly
leaves often result from
poor growing conditions
too much sun, too little water,
nutrient-deficient soil,
and too much heat or cold.
Dig up the plants and
reestablish them in
amended soil in a more
ideal location.
If you
must leave them where
they are, apply a balanced
fertilizer, form a basin
around them to hold water,
and increase the amount
of water they receive.
I'm Debra Lee Baldwin.
If you'd like more information,
go to debraleebaldwin.com.