We could get very technical about fertilizers, but we won't. If you
follow the few simple rules below, you'll do just great. There are 12 points
below....but be sure to follow at least the first 4
and
10-12 for houseplants
- Cheap fertilizer is not good and good fertilizer is
not cheap
Usually it is best to buy the most expensive
fertilizers (per pound of weight) that is available. Do not buy
brands (cost more) but buy contents so the most expensive bag of an
unknown brand is likely better than the same price compared against a
brand name product
Why? Because expensive fertilizers have more plant food value and
less bulk (filler). Many better fertilizers are time released
formulations that feed over 60-120 days rather than washing away after
1, 2 or 3 rains
Fertilizer bags are labeled with contents such as 8-2-10 or some
other set of 3 numbers. The first number is nitrogen content,
the second is the phosphorus content and the third number is
the potassium content. There are more
essential foods (see below)
Do not think that a bag that says 20-20-20 is automatically 10 times
better than a bag labeled 2-2-2. No plant would want 20-20-20, except maybe lawn grass.
You will want to get the right fertilizers
for your plants
Fertilize often. Once a year is (sorry to say)
stupid. Use the same amounts but spread the feedings into smaller meals.
Feeding 3, 4, even 6 times a year is way better, e.g. U-Florida
recommends 6X a year
Apply granular fertilizer like salt and pepper.
Sprinkle at and somewhat beyond the drip line. Apply enough to see
the fertilizer on the soil but not much more. Apply a width
depending on size of plant, e.g. a tree you might apply a foot wide,
small shrub, a few inches
The time to feed is when it's
warm and hot. In South Florida,
feeding #1 would be late winter, perhaps March 1st or so. Why feed
then? Because that is when plants start their growth period.
Feed often, all the way to September or October in Florida zone
10. Last feeding is August or September zone 9. Last feeding
in zone 8 would be August
If you live in cooler climates, follow
the same rules. Feed right at the start of warm weather and quit
about a month before cool weather returns
- Buy "acid forming" fertilizer for your
Ixoras
and Gardenias and all other acid (soil)
loving plants. Read labels and find one that usually says "for acid loving
plants" on the bag
If you have an Ixora hedge (and who doesn't?), you'll probably need to buy 2
or 3 bags. If you don't use proper fertilizer on Ixora, your plants will have very poor blooms and yellow foliage
- If you have citrus
trees, you'll want to buy at least one bag of
citrus fertilizer. Use palm food if citrus is not available
The latest recommendation for citrus is a bag labeled 8-3-9 or 8-2-10
and it should have at least 3% magnesium. See the back of the bag for other
nutrients (minor elements) and their quantities. Minor elements are critical for
citrus health. See our citrus article for more information
Citrus is not a tropical (as most people believe) but a Mediterranean plant.
South Florida soils are terrible for citrus. For good fruit
and healthy trees, buy a bag of citrus food
- The only remotely "universal" fertilizer type is
palm fertilizer
Palm fertilizer is
now the ONLY remaining fertilizer you can buy that reliably has "minor elements" in the mix.
Minor elements include iron, zinc,
manganese, magnesium, boron, etc..
In the past two years, even palm fertilizers have
degraded in content. Many palm fertilizers now are almost "junk" in
quality. Remember, cheap price = cheap contents
(food value)
The latest University of Florida recommendation for palms is to use 8-4-12. Palm fertilizer should
automatically include 3-4% of both magnesium and manganese
Critical:
Extra sensitive palms like pygmy date
palms, sagos,
queen palms, royal palm, foxtail and paurotis will probably die without these critical
nutrients. To be 100% sure, go ahead and by both magnesium and
manganese as separate supplements to apply when you apply regular
palm
fertilizer
Be safe. READ THE BACK LABEL
and get as many minor elements included as possible in your bag of
fertilizer
You may end up with a bag labeled "Rose Food" or a
bag labeled "Bloom Booster" or something else. Don't let these labels
influence your purchase
The more different minor elements, the better
The more quantity of
the minor elements, the better
The more usable minor elements, the better. For example,
there's iron and there's chelated iron, which is far more available to the plant. Expect
to pay more for the chelated iron content
Buy a bag with at least 6 minor elements. A bag
with 8, 10 or 12 minor elements is even better
>>>>>
The point is you can use good quality palm fertilizer on everything else
in your landscape and be pretty safe you're doing the right thing
Follow label directions for quantity
If you want to be 100% sure you've done all the right things for
your palms, also buy a manganese and a magnesium
supplement (more bags). ALL PALMS (except native Florida palms)
demand added magnesium and manganese for health. Follow label
instructions. To add magnesium you may purchase Epsom Salts at
your drug store. Epsom Salts is magnesium sulfate. Always
apply with a dose of your regular fertilizer for that plant (to prevent imbalance)
- In South Florida, plan on fertilizing at least 4 times a year from Spring through
October. As of 1997, The University of Florida recommends 6 times a
year is better, especially for palms
- If you have flowers, you'll also want to buy some
time release chemical fertilizer and/or
some organic fertilizer
Buy time released
pellets as the best chemical time released fertilizer. There are now many
brands of pellets so look for the contents - read the label. For
example, most stores stock a lot of high nitrogen
time release pellets. Formulations like 25-10-10 or any other 3
numbers with a high first number = a high nitrogen formulation. The
ONLY time that would be correct is on foliage plants (nothing but leaves).
For fruit and flowers, you want a low nitrogen
formulation. Something like 5-10-10 or similar. You can't burn
plants with time release pellets
Milorganite, we believe, is your best
granular organic fertilizer. Use Milorganite on delicate plants and all
plants which respond well to organic nutrients. Never use
Milorganite in potted plants
- Another good supplement is IRONITE.
Ironite really greens up plants (fast), but especially on plants which tend to yellow out.
Use on trees is also very good, but may be harmful to palms and
cycads. Try to find the dry, granular form of Ironite. Use
a little per label instructions. Over use is a killer and iron is
not a substitute for overall good fertilizer ingredients. Always use
only on plants with wood (not fiber, like palms and cycads
- If you have bromeliads, orchids, staghorn ferns or other air plants,
consider using Fish Emulsion fertilizer
Fish Emulsion is another organic fertilizer (ground up fish
parts) and works wonders on all plants. You can use "fish" anywhere and
everywhere, except maybe indoors. You won't like the smell, but Alaska
brand we buy locally can be used for indoor plants as well. It's a
sure thing as you can not burn or overdose using fish
We ignore the label which says 3-4 tablespoons per gallon every 3-4 weeks. Instead
we 1-2 tablespoons per gallon and use it with every watering on potted plants.
We also use it as a "tonic" for sick plants 2x or 3x strength over 2-3
waterings. You can also plant plants watering
them into your soil with
fish instead of plain water to promote quicker adaptation
There are also seaweed concoctions usually sold in highly concentrated
formulations. We used to be able to buy Roots Organic brand
which was a marvel. It cured every sick plant we every tried it on
and always used it in delicate transplants
We can not recommend any specific seaweed supplement but all the ones we
have tried work just fine. Some are used in the soil, other as a
foliar spray, some both. Read the label
- Keep all your fertilizers dry and away from children and pets. You know why
- Use liquid fertilizers indoors
if you must. Using time released pellet fertilizer is better, but liquids are OK for occasional use. All (chemical) liquid is bad because most products
contain large quantities of salts that will build up in your soil and on the surface of
your pots (a white hard residue that doesn't
wash away)
We get tons of email from people who are killing their plants with liquid fertilizer,
especially Miracle Grow (it's very advertised so many people buy). We guess they believe the ads or use too much, but rapid decline is the common complaint
We can also say that professionals in South Florida do not use Miracle Grow. Almost
all growers and nurserymen use Peters liquid, but NEVER as a main food. Almost all
use time release pellets and an occasional boost using Peters liquid fertilizer (blends).
- Almost as bad as using Miracle Grow the
wrong way is buying potting soil with fertilizers included
Yes, we know the claims about great growth, but we can say every test we
have made with these "soils" has killed every plant of every variety we
have tried (in pots). We also get lots of
email from folks using other brands of bagged soil with fertilizers included ...very often
with immediate leaf yellowing, leaf drop & other problems or death
Must be too strong; too fast a release. Sadly,
most store shelf space is
now devoted to the soils injected with crystals of chemical fertilizers,
so you have to shop even harder to find "clean" soil. You might
consider mixing fertilizer soils with Canadian peat moss to dilute the
concentration
- We have one more point about fertilizer and
that is about soil
In the wild, there is no fertilizer (added) and Nature's plants have been doing just fine
for millions of years. Wild plants get 100% of their nutrition from their
(native)
soil. Nature's soil is a highly
complex mixture of decayed plants, live and dead insects, bacteria, fungi, enzymes,
hormones, etc. Where people run into trouble is planting non-native
plants and using incompatible soils (compared to the native soil for each
plant you want)
First, never buy the cheap soils. You see
heavy 40 pound bags of "potting soil" or
"composted soil" as low as $1.29 a bag. This stuff is awful for
tropicals and deadly for almost all potted plants
You must buy something labeled "nursery
mix" or "pro mix" and the bag must weigh very little for its size. Never
buy the cheap stuff because it's no good. Expect to pay about $8-$12 for
two cubic feet of quality soil
The soil you want to buy
should contain
some or all of these parts:
- Canadian peat moss
- Pine bark chips
- Charcoal chips
- Composted manure
- Dehydrated composted manure
- Mushroom compost
- Perlite
- Vermiculite
The soil you buy should
NOT contain:
- Top soil
- Fertilizer
- Anything that came from a sewer plant
- Insecticide
- Fungicide
What you want is a Canadian peat moss based soil mix with added ingredients such
as pine bark chips, charcoal chips, perlite, seed hulls, composted manure
or dehydrated manure, etc. In general, the more ingredients,
the better. However, know that many of these soils are
sterile...having no insects, no bacteria,
no fungi, no enzymes, no hormones, etc
These quality soils are used by 100% of
professional growers here in South Florida. Soil is a major expense
for growers, but they know you can not grow good plants without good soil
Here we see a sign at Fairchild Tropical
Gardens that talks about the acidic mix for acid loving (soil) plants.
This mix is 50% silica sand, 35% peat moss and 15% composted pine bark.
By the way, the sign also says they dug down 2-5 feet
Commercially in bags, these soils are harder to find and are the most
expensive per bag and certainly per weight of bag. Like fertilizer,
the more expensive, the better. Locally, we like Lambert's pro mix
at about $8.50 for 2 cubic feet at Home
Depot. Soils to avoid are sold by the POUND, e.g. $1.49 for 40 lbs
Often we will add coarse sand to professional soil and as much as 50%.
We do this with true tropicals as they are used to a sandy (native) soil
and the resulting good drainage is always welcome. If coarse sand is
hard to find, use Perlite instead
Please shop for your fertilizers
locally, but
we offer some top quality foods
here only
because some folks can't find good fertilizers |