1 © 2011 Regents of the University of Minnesota. All rights reserved. 11 Houseplants MASTER GARDENER PROGRAM

2 © 2011 Regents of the University of Minnesota. All rights reserved. CLASS OBJECTIVES  Understand basic growth requirements of houseplants  Understand how various aspects of light affect plant growth  Know how to water indoor plants  Know what containers and soil to use  Become familiar with insects/diseases of houseplants

3 © 2011 Regents of the University of Minnesota. All rights reserved. WHY GROW HOUSEPLANTS?  Beauty

4 © 2011 Regents of the University of Minnesota. All rights reserved. WHY GROW HOUSEPLANTS?  To nurture a living thing

5 © 2011 Regents of the University of Minnesota. All rights reserved. WHY GROW HOUSEPLANTS?  As part of our interior design

6 © 2011 Regents of the University of Minnesota. All rights reserved. WHY GROW HOUSEPLANTS?  To live with green plants year round

7 © 2011 Regents of the University of Minnesota. All rights reserved. WHY GROW HOUSEPLANTS?  To clean the indoor air

8 © 2011 Regents of the University of Minnesota. All rights reserved. WHY GROW HOUSEPLANTS?  To provide fresh food (herbs) year round

9 © 2011 Regents of the University of Minnesota. All rights reserved. WHY GROW HOUSEPLANTS?  To use your creativity

10 © 2011 Regents of the University of Minnesota. All rights reserved. THERE IS NO SUCH THING AS A HOUSEPLANT!  Tropical Plant  Desert Plant  Annual/Tender Perennial Plant

11 © 2011 Regents of the University of Minnesota. All rights reserved. GOAL: REPLICATE NATURAL CONDITIONS

12 ENVIRONMENTAL FACTORS  Light  Water  Humidity  Soil  Nutrients

13 LIGHT—MOST CRITICAL Brightness and intensity vary by:  Exposure (North, South, East, West)  Distance from the light source  Window coverings, film/dirt on the window  Dust on leaves  Time of year  Artificial light

14 LIGHT  Intensity/brightness  Duration: hours of light  Quality: color or wavelength

15 WATERING Factors that affect frequency of watering:  Type of plant  Type of Container  Temperature  Humidity in the air  Potting medium

16 WATERING METHODS  Water when the plant needs it –Feel the soil –Water thoroughly  Use water at room temperature  If water is chlorinated allow it to stand 24 hours  Improve oxygen level by using Enki watering can

17 DIFFERENT WATERING METHODS  Some require consistently moist soil  Some require soil to dry out between watering  Avoid water on foliage  Let water run through

18 TOO WET/TOO DRY Overwatering symptoms:  Lower leaves turn yellow and drop  Oedema can develop  Adventitious roots on stems  Root rot Under watering symptoms:  Dry or brown leaf tips/margins  Leaves that turn brown and die  Plants become stunted or woody

19 © 2011 Regents of the University of Minnesota. All rights reserved. BASIC RULE OF WATERING ? If in doubt... don’t

20 HUMIDITY  Desert natives prefer dry air  Tropicals miss their rainforest

21 INCREASE HUMIDITY  Place plants in pebble filled trays  Group plants together  Place plant in a bathroom or near a kitchen sink  Running a humidifier  Move plants away from heat vents  Grow plants that require high humidity in a terrarium  Allow plants to spend time outside in the summer  Select plants that tolerate low humidity

22 CONTAINERS  Large enough to hold sufficient soil  Allows for proper watering – headspace  Non-Toxic  Provisions for Drainage  Attractive

23 CLAY POTS  Heavy, prevent tipping  Porous – good aeration  Overwatering less of a problem  Soil dries out faster  Mineral salts and algae may collect on exterior  Breakable  More expensive than plastic

24 PLASTIC POTS  Light-weight and easy to handle  Less expensive  Easily cleaned for reuse  Overwatering may be a problem  Often tip easily  Variability in aesthetic appearance

25 SOIL Soil provides both nutrients and physical support for the plant

26 ALL-PURPOSE POTTING SOIL  May be soil-less  Must be sterile  Is made of peat moss, compost, bark, perlite, sand, loam combinations

27 SPECIALTY POTTING MIXES  Orchids  Cacti  Palms  Bromeliads  Azaleas

28 FERTILIZATION HINTS  Fertilize every two weeks March through September with water soluble fertilizer at ½ the label rate.  Never fertilize when plants are dry  When using liquid solution make sure some runs out of the pot

29 © 2011 Regents of the University of Minnesota. All rights reserved. FERTILIZATION Symptoms of insufficient fertilizer:  Pale foliage (especially if Nitrogen is lacking)  Leaf loss  Few flowers  Stunted and unhealthy looking plants Symptoms of over fertilization:  Hard, stunted growth  Burned leaf margins  Poorly shaped leaves  Wilted leaves (when soil is wet)

30 © 2011 Regents of the University of Minnesota. All rights reserved. INSECT AND DISEASE CONTROL  Examine plants closely before purchasing for insects or disease  Isolate purchased plant for 2 weeks  Prune out any bug/disease infested portion of the plant  Treat plant for specific insect or disease  Never apply any chemicals to a moisture stressed plant  Avoid misting plants!

31 © 2011 Regents of the University of Minnesota. All rights reserved. CREDITS AND THANK YOU TO:  Presentation content and pictures provided by Sue, Hennepin County Master Gardener  Presentation formatting completed by Amy Johnson, Hennepin County Master Gardener  Information on container types and fertilizer signs/symptoms used from Carl F. Hoffman, Extension Horticulturalist for “Indoor Gardening” presentation

32 © 2011 Regents of the University of Minnesota. All rights reserved. The University of Minnesota is an equal opportunity educator and employer. In accordance with the Americans with Disabilities Act, this PowerPoint is available in alternative formats upon request. Direct requests to the Extension Store at Discover more at extension.umn.edu