PLANT DOCTORWhy do plants' leaves turn various shades of yellow?
Yellowing leaves on your plant can be confusing, frustrating and even annoying if you don’t know what the cause is.
You’re plant could be in a container or in the ground, and during the colder months, those yellow leaves seem to become more prominent.
One of the reasons your plant's leaves may be turning yellow is because all leaves have a limited life-span, and just before they drop, the nutrients are pulled out of the leaf turning it yellow.
But what about other problems?
Let’s find out we can do about yellowing leaves.
Talking with Steve Falcioni, General Manager www.ecoorganicgarden.com.au
If the new leaves are paler but the old leaves are still a bright green, it's generally a sign of nutrient deficiency.
If the veins are distinctly green and the space between the veins is yellow, then it's probably iron chlorosis or iron deficiency.
Did you know that iron deficiency is pretty common in acid loving plants such as roses, fruit trees, camellias and even vegetables.
In this case the young leaves are yellow and the veins are green.
Magnesium deficiency on the other hand is more common in citrus as well as camellias and vegetables. Again acid loving plants.
It can be confusing because there’s a third deficiency that looks like a worst cause iron deficiency caused by not enough zinc and manganese
However, there are a range of products you can buy to fix these deficiencies.
If you have any questions about yellowing leaves and are not sure what the problem is, why not email firstname.lastname@example.org or write in to 2RRR P.O. Box 644 Gladesville NSW 1675.
VEGETABLE HEROES Aloe veraThe botanical name of Aloe vera is Aloe barbadensis Miller.
Aloe vera’s use can be traced back 6,000 years to early Egypt, where the plant was depicted on stone carvings.
Known as the “plant of immortality,” aloe was presented as a burial gift to deceased pharaohs.
The name Aloe vera derives from the Arabic word “Alloeh” meaning “shining bitter substance,” while “vera” in Latin means “true.”
Did you know that the word Aloe in Sanskrit means Goddess?
Because of aloe’s well-known healing properties for the skin, aloe is one of the primary compounds used in the cosmetic industry.
There are even Aloe vera drinks that you can buy, or you can use the juice straight from the plant.
What's So Good About Aloe vera?
Aloe leaves contain a clear gel that is often used as a topical ointment.
The yellow sap that oozes from the base of the leaf when it is cut is called bitter aloes.
This bitter sap when dried is called latex.
This bitter sap contains anthraquinones, used quite a lot in medicines that act as a strong laxative.
Be warned though, don’t feel you can make your own oral medicines from Aloe and I’m not recommending that you drink the gel straight from the leaf either.
The reason is because not only is aloe vera juice pungent to taste, but there is no scientific evidence that drinking the juice does anything.
On the other hand, Aloe plants improve air quality, and when grown in pots inside the house, help remove toxins from the atmosphere.
So what is Aloe vera?
Aloe vera isn’t a cactus but a low growing spreading, xerophytic, succulent.
It grows mainly in the dry regions of Africa, the Arabian peninsula and nearby islands such as the Canary Islands and Madagascar.
|Aloe barbadensis "Miller"|
The Aloe plant is grown in warm tropical areas and because the leaves consist of 95% water, they’re extremely frost tender.
However the root can survive freezing air temperatures, so long as the ground is not frozen and the root destroyed.
On the other hand, Aloe vera doesn’t grow all that big and can be easily moved indoors in colder climates if outside temperatures are less than 5°C.
Place it near a sunny windowsill and it will survive for a few weeks or a couple of months if it needs to.
On the upside, for those gardeners living in warm climates, Aloe vera can cope with temperatures in the high 30’s and can even withstand severe drought.
Don’t water during the winter months if your plant is able to grow outdoors because it’s practically dormant.
Aloe vera tolerates either full or partial sun for at least 8 – 10 hours a day, but will require a little more frequent watering in full sun.
If you’re area receives a lot of rain, you may find that the plant turns to mush so move it under cover.
During the summer months, the soil should be completely soaked, but then be allowed to dry again before re-watering.
If you’re growing your Aloe vera in a pot, because Aloes have a shallow, spreading root system, when it‘s time to repot choose a wide container, rather than a deep one.
Always use planters or containers with a drainage hole, or put a 3-4 cm layer of gravel in the bottom of the pot so it receives sufficient drainage.
Use a good commercial potting mix with extra perlite, charcoal, or coarse sand added.
Or you could use a packaged 'cacti mix' soil.
Fertilising is only necessary once a year in spring but use only half strength. Aloe plants have relatively short roots and heavy leaves, so it’s best to move your plant to a heavier pot when they become top-heavy and tip over.
If Aloe vera runs out of space for its roots to grow, it may start to produce "pups" that can be moved to their own pot .
Growing New Plants
New Aloe Vera plants are grown by removing these offsets which are produced around the base of mature plants, when they are about 5 - 7cm tall (or larger). They can also be grown from seed.
|Aloe Vera pups or offsets|
Keeping an Aloe vera plant at home is one of the easiest ways to get the freshest and most concentrated gel.
Plant Problems Solved
If the leaves start getting burnt on hot days, you ‘ll definitely need to move your plant to a location with light shade.
If the leaves are growing flat and low, that means the need more sunlight. Aloe vera leaves should grow upward or outward at an angle, toward the sunlight.
Growing low to the ground or growing flat outward, is an indication that the plant is probably not receiving enough sun.
Move it to a sunnier area.
If it’s indoors, consider keeping it outdoors during daylight hours.
If the leaves turn yellow or fall apart, stop watering.
Yellowed or "melting" leaves are suffering due to excess water.
Stop watering altogether for the next week (or two weeks during the dormant season), and water less often after that.
You can remove the discoloured leaves from the plant without doing any damage.
Tip:Remember, water it only when the soil has become dry.
Using the Leaf
Using aloe vera gel, that’s the inner portion of the leaf, topically is OK straight from the leaf.
TIP: To use the gel, break off a leaf and cut it lengthwise to expose the inner layer.
Scoop the gel out and apply generously to the area needing treatment.
Discard whatever gel is not used immediately, as it will degenerate quickly.
Why is it good for you?
Aloe Vera contains many vitamins including A, C, E, folic acid, choline, B1, B2, B3 (niacin), B6. Aloe Vera is also one of the few plants that contains vitamin B12.
Soothes and heals sunburns because it contains cooling properties similar to menthol.
Takes the sting or itch out of insect bites.
Use it on those joints that have osteoarthritis.
Aloe gel has not been shown to prevent burns from radiation therapy.
AND THAT WAS YOUR VEGETABLE HERO SEGMENT FOR TODAY!
DESIGN ELEMENTStalking with Landscape Designer Glenice Buck http://glenicebuckdesigns.com.au/
Last week a new series about re-working a garden on a farm property.
Today, Glenice works out where to put the fences to mark the garden.
|Peppercorn Tree Drive-way photo Glenice Buck|
Finding out what challenges they faced. Was the soil be any good? Did they leave the existing trees? Was there a weed problem?
As the property is a working farm, Glenice said the she knew that for any plants to be able to grow, they needed to fence off the garden area so that the sheep and cattle wouldn't eat the plants.
The existing mature trees are about 100 years old and need to be considered as well.
Do they make up the garden?
Let’s find out some more in part 2….
You would think that you should just get in there and start planting things without worrying too much about the soil and stuff.
Not so. If you don’t get the soil right, the aspect right and the drainage right, your putting yourself onto a patch of unhappy gardening. You also have to consider the climate to know what plants will survive.
|Truck arriving with first load of plants photo Glenice Buck|
The climate in the area has a temperature range of -4 C to mid 40's C
They also experience heavy frosts in winter and heat-waves in summer.
Average rainfall is 24 inches per year.
The weeds included Marshmallow weed, that had to be eradicated before the first truck of plants arrived.
PLANT OF THE WEEKwith Jeremy Critchley owner of www.thegreengallery.com.au and Karen Smith, editor www.hortjournal.com.au
Ever heard of a Twinspur? Yes it’s a plant with heart shaped leaves and flowers not unlike a Snapdragon because Snapdragons are its cousin.
Native of South Africa, these plants are perennial in warm and temperate climates and possibly even survive longer than annuals in cooler climates.
Newer varieties have names like Apple Blossom, Little Charmer, Apricot and Snow.
What is this plant? Let’s find out …
Diascias have been around for many years and in the past have been known as Dutchman's Britches!
Why Dutchman's Britches?
Because the lower part of the flowers looks like those blowsy pants that Dutchmen used to wear in the 19th century.
Whether you want to call them Twinspurs or Dutchman's Britches, these plants are fast growing garden plants in most well-draining garden soils where the beds have been well prepared with some compost incorporated in the bed before planting.
Use an organic fertiliser like Blood and Bone pelleted manures.
Also fortnightly applications of a weak solution of a balanced liquid fertilizer will help them along.
When flowering seems to be fading the plants can be pruned to rejuvenate them and get a second flush of flowers.
Tip: Plants in pots seem to last for years and years. My friend Sabrina says she had one survive for at least 10 years! Now that's value.