Transcript Soil VGB outline 1

Soil: It’s Important!
Vegetable Gardening for Beginners, 10 February 2016
Karen Leu, Education Intern, UT Gardens, and Master Gardener
Learning Objectives
 Understanding of the nutrients
 Brief introduction to hydroponics
 How to take and read a soil test
 Understanding applications of different types of fertilizer
 Composting
 Long term soil building.
Introduction
 Nutrients in the soil: Key element for plant survival
 But do we even need soil?
Part 0.5
A few words about hydroponics and soilless growing.
Hydroponics and Aeroponics: More than
just science fiction.
Pros
 Uses less fertilizer than the same
plants in soil.
Cons
 Can be expensive to start up.
 Possibly fewer pesticides.
 Not the most “traditional”
alternative.
 Usually more plants in a smaller
space
 Some systems need to be
plugged in to work.
Imagine a hydroponics urban utopia
Pros
Cons
Hydroponics can teach us about soil
 Let’s look at science fiction!
 Contents of soil:
 Mineral content (sand, silt)
 Organic content (fertilizer)
 Lack of toxins
Let’s look at it another way
 The big three, Nitrogen (N), Phosphorous (P), and Potassium (K)
 The air-and-soil chemicals Carbon, Hydrogen, and Oxygen
 The micronutrients.
 Calcium, magnesium, sulfur
 boron (B), zinc (Zn), manganese (Mn), iron (Fe), copper (Cu), molybdenum (Mo), chlorine (Cl)
 pH and other characteristics
Part 1: Soil and its nutrients
So how does this apply to me?
How does your soil measure up?
 What elements are in your soil? The extension service will accurately test this for you!
 How to collect soil: Small amounts representing your whole garden. Mix and extract one
cup.
What do you do with your results?
 https://ag.tennessee.edu/spp/Documents/soilrptexplanation.pdf
What do you do with your results?
 Here’s a calculation to show how much fertilizer of different types to add to
correct fertility problems from your soil test.
 Equally important, follow the instructions on the fertilizer.
 This saves nitrogen and other nutrients from washing off and polluting local
waterways.
 There are different guidelines to follow to change the pH of your soil. Again,
follow the instruction on the lime (most TN soils would be more acidic than
alkaline).
 Be aware that changes in pH and fertility caused by adding lime or fertilizer will
not be permanent.
Different Types of Fertilizer
 Chemical fertilizers come from mines.
 Organic fertilizers generally come from things that were once alive.
 Granular fertilizers can be organic or chemical, but this is the general way to apply fertilizer
 Time-release fertilizers are handy for long-lived plants.
 Water-soluble fertilizers can be very useful for providing a quick boost of nutrients to
struggling plants.
 Some brand names: Osmocote, Miracle Grow, Espoma, Jobe’s, Neptune’s Harvest.
Take care of your soil for the long run
 Once you’ve done the major adjustments with your soil test, for the next few years, you
can count on small doses of compost and organic amendments to keep your soil healthy.
 Keep the level of organic matter in your soil high in order to let humus do the work for you!
Humus is a miracle molecule that stores nutrients in the soil, and slowly gives them up to
plants, like a battery.
 Consider making permanent beds so that you will not step on the ground around your
plants so much. Compaction is a big issue for plants. Plant roots grow a lot better in fluffier
soil
Applying fertilizer during the season
 Nitrogen deficiency is the easiest to spot,
since an optimal level of nitrogen will give
your plants nice green leaves.
 Iron deficiency also causes yellow leaves.
 Side-dress the plants.
Photo: University of Oklahoma
Noticing nutrient imbalances
 Lack of phosphorous will create purple
veins on the leaves or entire purple
leaves.
 If left untreated, fruits will be small and
bitter.
 Happens if the soil is too cold or if soil is
not fertile enough.
Photo: Texas A&M
Noticing nutrient imblances
 Iron chlorosis has a signature style where
the leaf is yellowed or bleached, but the
veins of the leaves remain green.
 The pH value of your soil may be
imbalanced. (Soil too alkaline)
 If the pH is alright, then you need more
iron in your soil.
Photo: Clemson U
Part 2: Compost
From trash to treasure
From Dust to Dust
 Recycling kitchen waste is as easy as
putting it in the ground, or in the middle
of a huge pile of leaves.
 But compost does the job for you faster,
with an end product many know as
“black gold”
How does compost work?
 Home garden composting relies on the fact that decomposing plant matter creates heat.
 Certain bacteria thrive in this heat, and they are very active.
 Decomposition happens more quickly.
 The temperatures of 130*F to 150*F kill weed seeds and reduce amounts of other plant
pathogens.
Three rules of compost
 Keep the pile moist
 Turn the pile frequently
 Keep the right ratio of “brown” to “green” materials.
Rule One
 When creating your compost heap, keep a hose or watering can handy to moisten the
pile.
 Don’t make it too wet.
 Make sure the pile is big enough to keep from drying out. My extension agent from my
home county recommended a minimum dimension of 3’x 3’x 3’ and at least one
dimension being five feet would be better.
Rule Two
 Turning a pile can increase aeration in the compost, speeding up the aerobic bacteria.
 Introduces the undecomposed material on the outside to the bacteria on the inside.
Rule Three
 Brown elements are those high in carbon
 Fall leaves, dried grass, straw, newspaper, wood chips
 Green elements is another name for those with more nitrogen
 Fresh lawn trimmings, manure of herbivores, kitchen scraps.
 Not recommended to use meat scraps or manure from pets. This could attract scavengers
and increase pathogens like E. coli.
Vermicomposting
 Eisenia fetida, red worms
 Use a plastic storage tub, drill holes around the top.
 Use torn newspapers for “bedding”
 Recycle your kitchen scraps!
 Again, no meat or dairy.
 Worms don’t really like citrus or onions either.
 Worm castings are a very rich soil amendment.
Types of purchased compost
 When adding some types of organic matter to your soil, you may get a problem with too
much phosphorous. To correct this problem, check that any amendments that you buy
are balanced and have a good amount of nitrogen in them.
 Mushroom compost- take care not to salt your garden.
 Composted manure- safe to apply around growing plants. Uncomposted manure is not as
safe.
 Peat moss and coir are all carbon- use to enrich your soil.
Part 2.5
Long-Term Soil Building
Hugelkultur
 The European practice of using wood to enrich soil.
 Use whatever wood you like. Firewood that’s a little past gone is a good choice.
 Lay on the ground or in a shallow trench.
 Plants grown on top will benefit from stored moisture and humus.
Nutrient accumulators
Certain plants are able to gather nutrients from deep in
the ground and bring them up to the surface. The long
and thick taproots of these plants are also good for
breaking up the soil and are very useful in no-till
gardens.
Another purpose would be to pull a certain mineral out
of the soil that has too much, such as too much
phosphorous.
But more scientific research needs to be done in this
field, as the proof is mostly anecdotal.
Daikon Radishes
Plant nitrogen-fixing perennials
 Locust trees,
 Autumn olive shrubs,
 Red clover, white clover
Plant your lawn in white clover!
HIGH NITROGEN
TREES, NATIVE
TREES, NON-NATIVE
Alnus glutinosa, Elaeagnus
angustifolia
SHRUBS, NATIVE
SHRUBS, NON-NATIVE
MEDIUM NITROGEN
LOW NITROGEN
Robinia pseudoacacia
Catalpa speciosa (*), Gladitsia
aquatica (*), Gymnocladus dioicus (*)
Albizia julibrussin
Alnus incana, A. maritima, A. serrulata, Amorpha
fruticosa, A. glabra, Elaeagnus commutata, Morella
pensylvanica (=Myrica), Senna marilandica,
Shepherdia argentea, S. canadensis
Cytisus scoparius
VINES, NATIVE
Acacia constricta, Alnus viridis crispa,
A. incana rugosa, Ceanothus
americanus, Comptonia perigrina,
Myrica gale,
Caragana arborescens, Elaeagnus umbellata
Apios americana, Lathyrus japonicus, Wisteria
frutescens
Vicia americana
VINES, NON-NATIVE
Pueraria lobata (**)
Lathyrus tuberosus, Vicia cracca
Vicia sativa
HERBS, NATIVE
Dalea candida
Amorpha canescens, Dalea formosa, Dryas
octopetala, Lespedeza hirta, L. capitata,
Hedysarum boreale
Astragalus canadensis, Baptisia
tinctoria, Dalea purpurea, Desmanthus
illinoiensis, Desmodium paniculatum, D.
perplexum, D. tortuosum, Glycyrrhiza
lepidota,
HERBS, NON-NATIVE
Astragalus cicer, Medicago sativa, Lotus corniculatus, Melilotus indicus, Securigera
Trifolium repens
varia (=Coronilla), Trifolium pratense