Interior Plantscapes IPM PA

What might cause brown or scorched leaf tips?

poor root health, specific nutrient toxicities, low humidity, pesticide or mechanical injury

Leaf spots, blotches, blemishes, blisters, or scabby spots

symptoms of intense light (sunburns) associated with recent move, excessive dryness, chilling injury chemical spray injury, overwatering, infections

Older leaves yellow-green

nitrogen deficiency, root bound, soil compaction, insufficient light, natural aging.

Newer leaves yellow-green

soil acidity imbalance, element imbalance.

All leaves yellow-green

too much light, insufficient fertilization, high temperatures, insect infestation or root rot.

causes for leaf drop

improper watering, poor drainage, excessive fertilizer, compacted soil, root rot, environmental changes

causes for wilting/dropping foliage

improper watering, poor drainage, compaction, excess fertilizer, root rot.

Reasons for brown roots, roots massed at top or bottom of pot

improper watering, poor drainage, compaction, root bound, toxic chemicals in soil, root rot

Yellowed leaves with speckling, webbing near growing plants, leaves water bronzed

spider mites

Leaves on stems with sticky substance, mold growing on leaves, brown or white objects in crotches of branches

scale or mealybug infestation

Low light intensity

25 to 75 foot candles.

Medium light intensity

75 to 150 foot candles

High light intensity

150 to 1,000 foot candles

Light compensation point

the minimum light level at which the amount of food produced by photosynthesis is equal to the amount of food consumed during respiration.

Which plants require more frequent watering?

plants with large or very thin leaves.

How does pot size change watering needs?

a large plant in a small pot will need water more often than a small plant in a large pot.

What type of container evaporates water most quickly?

untreated porous clay pot.

How often will most plant installations need to be watered??

once every 7 to 10 days

What time of day should you water plants?

early in the day

what pH reduces leaf spotting?

6.0

What is tiny feet?

When foliage reacts to high levels of fertilizer, producing large tops but disproportionately small root mass.

What’s the maximum amount of times you should fertilize an interior plant?

4 times a year

Abiotic disorders are caused by what?

environmental, cultural, and non-living things

Biotic diseases are caused by what?

living pathogenic micro-organisms such as fungi, bacteria, viruses, or nematodes.

Examples of abiotic disorder symptoms

reduced vigor, yellowing leaves, leaf drops, rapid death.

What is the most prevalent pathogen of indoor plants?

fungi

Systemic infections

occur in the plant’s vascular system.

Localized infections

appear as leaf or stem lesions.

Symptoms of anthracnose

lesions form on leaf or stem, limited in size, often have raised edge

Symptoms of cephalasporium leaf spot

young leaves develop small red spots with dark edges, fungus feeding insects enter wounds

Cercospora leaf spot symptoms

pinpoint lesion on underside of leaves resembling edema, small red brown lesions with pale edges.

Fusarium Leaf spot

small red to brown lesions with pale edges, affected leaves turn yellow and fall

Gray mold or botrytis Blight symptoms

attacks growing point, yellow to red rounded or oval leaf spots, fuzzy gray or cream colored fruiting bodies

Phyllosticta Leaf spot symptoms

irregular spots with brown centers and yellow halos

Powdery mildew symptoms

grey white spots or patches on upper leaf surface.

Bacterial leaf spot symptoms

spots from pinpoint size merge to cover large areas, except for midrib or leaves

Erwinia

distinct spots on blighted leaves mushy foul smelling rot of main stem, rapid mushy leaf collapse

Wet rot symptoms

begin at root tips, move toward stem, roots turn brown to black, outer layer.

Dry rots

source of damping off in seedlings, older plants develop dry reddish brown lesions at the soil lines.

Chrysanthemum aphid

dark colored, hosted by chrysanthemum only

Green peach aphid

spinach, potato, and peaches are preferred hosts

Biological control for aphids

lacewing larva or ladybugs, syrphid flies, damsel bugs, wasps, parasitic fungi.

Hosts for melon or cotton aphid

melody, okra, hops, strawberries, beans, spinach, tomatoes, clover, asparagus, ground ivy, begonia

Fungus gnat control

clean cultural practices, decay pots of sprouting grain decoy then boiling eggs, predatory nematodes, mites, and rove beetles, pesticides

Shore flies damage

primarily excrement , harmless but difficult to control.

Shore fly management strategies

avoiding excess water, pesticides, removing algae,

mealybug damage

sooty mold honeydew, premature leaf drop

Mealybug management strategies

discard infested plants, biological control is more effective.

Bread mites damage

leaves curl downward and turn coppery and purplish, hardened and distorted growth.

Bread mites management strategies

disinfect tools between usage, biologic control, miticides.

Spider mites management strategies

spray with water, pesticides

Scale insect management strategies

horticultural oils,

What is the most frequently encountered scale insects on indoor plants?

brown soft scale

A soil pH imbalance or trace element imbalance are possible causes of what plant symptom?

Newer leaves yellow

What will not help control fungus gnat infestations?

Disinfecting tools after working with infected plants

When would the release of natural enemies be the most appropriate?

when pest populations are not already causing damage

True or false, whiteflies cannot transmit diseases?

false

What plants do whiteflies prefer?

poinsettia, chrysanthemum, fuschia, and tomato plants.

What disease is associated with small to red brown lesions with pale edges, affecting leaves to turn yellow and fall?

Fusarium Leaf Spot

Which pest has razor sharp mouthparts that can cause damage to ornamental plants similar to thrips and lacebugs?

Mites

Predatory mites effective on aphids.

false

What are predatory mites effective in controlling?

fungus gnats, shore flies, mites, and thrips.