Oxalis tuberosa - Oca

Latin plant name Oxalis tuberosa Common plant name Oca Plant type Perennial herbaceous plant Size (meters) < 1m Distinguishing features The plant is not known in the wild, but populations of wild Oxalis species that bear smaller tubers are known from four areas of the central Andean region. Oca was introduced to Europe in 1830 as a competitor to the potato. Oca is cultivated primarily for its edible stem tuber, but the leaves and young shoots can be eaten as a green vegetable also. Andean communities have various methods to process and prepare tubers, and in Mexico oca is eaten raw with salt, lemon, and hot pepper. Oca is fairly high in oxalates, concentrated in the skin, and the bioavailability of oxalate appears to be similar to spinach. Oca is one of the important staple crops of the Andean highlands, due to its easy propagation, and tolerance for poor soil, high altitude and harsh climates. Oca needs a long growing season, and is day length dependent, forming tubers when the day length shortens in autumn (around March in the Andes). In addition, oca requires climates with average temperatures of approximately 10 to 12°C (range: 4°C to17°C) and average precipitation of 700 to 885 millimeters per year. In areas with harsh winter climates, early frosts may cut back the foliage before the tubers have a chance to form. In tropical areas where the days are unchanging in length, oca will not set a crop successfully.

Planting a tree

To plant a tree we need to dig a hole three times the size of the pot of the tree.

Once the hole is digged we will untighten the roots of the tree so they do not go circular and they can grow properly.

We will put some water into the hole to see if it drains. If it does we put some compost on the bottom, if it does not drain we will place some pebbles or sand and then the compost.

We lay the roots on the hole and cover with soil avoiding to leave air in the middle.

We press the soil on the top and put some more compost over it.

We can stake the tree to help it grow straight even if there are hard winds. We will place the stake on the side of the dominant wind, at a distance of 20cm of the tree and we will tie the stake to the tree with rubber cords to allow the tree to have flexibility when it gets the wind.

Never stake a tree longer than two years. Its root should develop properly to give enough strength to the tree to hold by its own roots.

The tree we planted is a cherry tree.

Perlite

Perlite is an amorphous volcanic glass that has a relatively high water content, typically formed by the hydration of obsidian. It occurs naturally and has the unusual property of greatly expanding when heated sufficiently. It is an industrial mineral and a commercial product useful for its light weight after processing.

Perlite is a non-renewable resource. The world reserves of perlite are estimated at 700 million tonnes.

In horticulture, perlite can be used as a soil amendment or alone as a medium for hydroponics or for starting cuttings. When used as an amendment it has high permeability / low water retention and helps prevent soil compaction.

Perlite provides extremely efficient increase in aeration as a consequence of its high air filed pore space. It produces a well drained environment for root growth.

Vermiculate

Vermiculite is a hydrous, silicate mineral that is classified as a phyllosilicate and that expands greatly when heated. Exfoliation occurs when the mineral is heated sufficiently, and the effect is routinely produced in commercial furnaces.

Vermiculite encourages quicker germination and improved seedling growth. It absorbs nutrients preventing them from being washed out and then releases them to the plant root.

Vermiculite can be used in different ways:

• Soilless growing media: exfoliated vermiculite is combined with other materials such as peat or composted pine bark compost to produce soilless growing media for the professional horticulturalist and for the home gardener. These mixes promote faster root growth and gives quick anchorage to young roots. The mixture helps retain air, plant food and moisture, releasing them as the plant requires them. These mixes were pioneered by Boodley and Sheldrake
• Seed germination: either used alone or mixed with soil or peat, vermiculite is used to germinate seeds. Very little watering is required. When vermiculite is used alone, seedlings should be fed with a weak fertilizer solution when the first true leaves appear. A tablespoon of soluble fertilizer per one imperial gallon (3.78 : 1) of water is the recommended mix
• Storing bulbs and root crops: pour vermiculite around bulbs placed in container. If clumps are dug, allow to dry for a few hours in the sun and then place in cartons or bushel baskets and cover with vermiculite. The absorptive power of vermiculite acts as a regulator that prevents mildew and moisture fluctuation during the storage period. It will not absorb moisture from the inside of stored tubers, but it does take up free water from the outside, preventing storage rot.
• As a soil conditioner: Where the native soil is heavy or sticky, gentle mixing of vermiculite up to one-half the volume of the soil is recommended. This creates air channels and allows the soil mix to breathe. Mixing vermiculite in flower and vegetable gardens or in potted plants will provide the necessary air to maintain vigorous plant growth. Where soils are sandy, mixing of vermiculite into the soil will allow the soil to hold water and air needed for growth.

Planting cuttings

When we take cutting from a plant we should plant them in the next half an hour. We can put them in water till we work with them.

Before planting them we can deep the cutting into rooting compound first.

We will have to create the proper mix of soil to put into the pot. It should contain:

• Soil
• Sand
• Compost
• Vermiculate or perlite

Once we have the mix we will fill the potts and plant the cuttings in the perimeter of a pot.

The cuttings should be in the pot at least for one year and then we can move it to another pot where they should be another year. After two years they can be moved to their final place.

Rooting compound

Synthetic plant hormones (PGR) are commonly used in a number of different techniques involving plant propagation from cuttings, grafting, micropropagation, and tissue culture.

The propagation of plants by cuttings of fully developed leaves, stems, or roots is performed by gardeners utilizing auxin as a rooting compound applied to the cut surface; the auxins are taken into the plant and promote root initiation. In grafting, auxin promotes callus tissue formation, which joins the surfaces of the graft together. In micropropagation, different PGRs are used to promote multiplication and then rooting of new plantlets. In the tissue-culturing of plant cells, PGRs are used to produce callus growth, multiplication, and rooting.

We can create our own rooting compound

Just as in humans, hormones stimulate various functions in plant growth. The first hormone discovered to cause root growth is called auxin, and the synthetic version of auxin is what we find in commercially sold compounds today.

The willow plant is a natural source of auxin. Therefore, it can be very easy to make up a fresh batch of homemade rooting compound whenever you need to plant some new cuttings.

Gather a handful of willow branch tips 

1. Chop or mash into smaller pieces 
2. Fill small container with pieces 
3. Fill container with water & allow to sit overnight 
4. Remove willow pieces 
5. Dip cutting into the water, covering the stem 
6. Put cutting into your potting mix (or moist sand) 
7. Cover with a plastic bag to retain moisture 
8. After roots form, re-pot

Also, don't get rid of the willow water when you're done with your cuttings. Save it to water your plants!

If you don't have access to willow, dissolve a few aspirins in a jar of water. Aspirin is made from willow bark, so it can have the same effect as the willow water.

Pruning a tree

Scar in the bark due to wrong pruning

When we prune a tree we have to be careful not to make scars on the bark. If the pruning of a branch is done to close to the bark, it will leave a scar in the bark and the inner part of the trunk will be exposed to air, therefore to fungi and roteness.







When pruning a branch we should always leave at least 2-3 cm of the branch out of the trunk, so when the bark reabsorbes it, does not make any scar in the tree.

Proper pruning leaving 2-3cm of distance to the trunk

How it should look after pruning

Scar due to a too tight staking of the tree

Other scars in the tree may be done by a bad staking. It we stake the tree too tight or with a hard material that is not rubber, the wind will make the string rub the bark and cause a scar like the one shown in the photo.

School hedge

We have planted a hedge to give some shelter to the school orchard.

We used:

• 6 rosa rugosa
• 6 berberis purpurea
• 7 cotoneaster bulatus
• 21 privet legostrum
• 22 Common Holly

That is a total of 62 plants that will allow as to have a double row of 31 plants each.

The lenght of the hedge is 6meters+15 meters that makes a total of 19 meters.

19/31=0.6m=2 feet

The distance between the plants will be of 2 feet in each of the two rows with a gap of 1 foot in between both rows.

With a string and some pegs we marked the position of each of the plants on each of the two rows.

We divided into three groups, one will dig square holes, the other will do round holes with the auger and the last will dig a trench.

TRENCH WORK

AUGER HOLES


SQUARE HOLES

Planting a hedge

A hedge can be planted to create shelter for the beds of a veg garden or an orchard.

To plant the hedge we will:

1. Clear the surface
2. Distribute the plants along the surface
3. Prepare the planting holes
4. Plant the trees

To clear the surface we will need:

• Strimmer
• Hedge clippers
• Spade
• Lawnmower
• Knapsack sprayer (after 10 days of clearing the surface)

To prepare the planting hole we will need:

• Auger
• Spade
• Shovel
• Wheelbarrow
• Measuring tape
• Post and wire
• String and pegs to get them into a line

The holes could be done:

1. Trench: It is the old method so it will take longer to prepare. Once the trench is been digged put some compost and lay the bareroot plants on the trench. Put back the soil that had been taken out from the trench and make the trees stand upwards. Press the soil around the tree.
2. Square holes: Dig a square hole bigger than the pot we are planting. Place some compost on the bottom of the hole and then place the tree. Fill the hole with soil and press around the tree to compact the soil and avoid air getting into the roots.
3. T cuts: Make a T-cut with the spade and slide the roots of the tree from the side so the roots are in the right position. It is the method that will give the minimal disturbance to the soil. It will not bring new weeds.
4. Auger: A round hole is not ideal because it can cause the roots go circular and die. The benefit from an auger is the speed and that is the reason why it is used by most of the gardeners.

Ethylene

Plants are sensible to smell and gases.

There is a gas produced by the plants called Ethylene. It is a natural plant hormone used to force the ripening of fruits.

Ethylene production is regulated by a variety of developmental and environmental factors. During the life of the plant, ethylene production is induced during certain stages of growth such as germination, ripening of fruits, abscission of leaves, and senescence of flowers. Ethylene production can also be induced by a variety of external aspects such as mechanical wounding, environmental stresses, and certain chemicals including auxin and other regulators.

What is actually caused by the gas may depend on the tissue affected as well as environmental conditions. In the evolution of plants, ethylene would simply be a message that was coopted for unrelated uses by plants during different periods of the evolutionary development.

List of plant responses to ethylene

• Seedling triple response, thickening and shortening of hypocotyl with pronounced apical hook.
• In pollination, when the pollen reaches the stigma, the precursor of the ethylene, ACC, is secreted to the petal, the ACC releases ethylene with ACC oxidase.
• Stimulates leaf and flower senescence
• Stimulates senescence of mature xylem cells in preparation for plant use
• Induces leaf abscission
• Induces seed germination
• Induces root hair growth — increasing the efficiency of water and mineral absorption
• Induces the growth of adventitious roots during flooding
• Stimulates epinasty — leaf petiole grows out, leaf hangs down and curls into itself
• Stimulates fruit ripening
• Induces a climacteric rise in respiration in some fruit which causes a release of additional ethylene.
• Affects gravitropism
• Stimulates nutational bending
• Inhibits stem growth and stimulates stem and cell broadening and lateral branch growth outside of seedling stage 
• Interference with auxin transport
• Inhibits shoot growth and stomatal closing except in some water plants or habitually flooded ones such as some rice varieties, where the opposite occurs
• Induces flowering in pineapples
• Inhibits short day induced flower initiation

In the prairies of North America the grass will use the ethylene to ensure their survival. When the buffallos are coming to the prairie and eating the grass it will create ethylene that will be taken downwind to tell the grass there that it has to produce seeds and put them to the ground to ensure that next year the seeds will grow again.

It is the same in a forest. The outside part of the forest will get the first cold weather of the winter season. The trees in the outside circle will turn their leaves into yellow and will generate ethylene to send the message to the inner trees that they have to turn their leaves colour in order to loose the leaves and not get frozen and die.

The ethylene will:

1. Ripen the apples, tomatoes, potatoes. Potatoes and apples should never be stored in the same room as the ethylene from the apple will cause the potatoes to sprout.
2. Make the grass produce seeds. The dandelion produces a lot of ethylene, that is why it is usually taken out in a garden to avoid the grass go seedly.

Polyethylene is a synthetic material. It has a similar structure as the ethylene, but it is not the solid form of ethylene.

Making charcoal

Timber that is not going to be used can be converted into charcoal that would be a clean heat source.

To make charcoal we need a metal barrel, the best would be of 4 feet tall and 10 feet of diameter.

We feel the barrel up with logs of around 50 cm, it can be fresh timber, it doesn't have to be dry.

When the barrel it's full we light a slow fire under the barrel for 3-4 days and we let it cool down for one week.

Willow wood it is very good to make charcoal. With small pieces of wood we can make charcoal drawing sticks.

Pollination

It is always good to encourage pollination. There are some plants that will attract hoverflies and bees that are the insects that pollinate the best.

The plants that best attract them are:

- Marigold
- Nasturtiums

It is good to plant any of the above close to the tomatoes to ease the pollination.

Frost

When watering the plants to pevent form the harmful effects of frost, the watering must be done during the day and the water should go to the soil, never to the leaves, as they will keep the water and it could get frosted.

Dormant plants do not need to be protected that much as their activity would practically stop during the winter time.

When covering a plant to protect it from frost, plastic would retain some heat but not a large amount, it is better to cover the plants with a fleece.


How to cover a plant with a fleece

Tender plants would need to be protected from frost. To cover them we have to take into account that the soil will absorb heat during the day and give it back during the night time. So the fleece has to be placed over the plant during the night, and taket away during the day.


During the high sun of the winter (2-3 pm) the soil will absorb the most heat, so it's good to have soil iwhtou any cover (fleece or mulch).


During the early morning (5-7 am) it's good to have the soil covered because the soil will loose the heat faster.

Bulbs

Bulbs should be planted from September to October.

Bulbs reproduce under the ground, if they are not taken out every year they will multiply too much and will be too compacted, not having enough space to let the plant grow properly what will mean less flowering.

It is good to take the bulbs out of the ground at least every other year.

Here is a guide for bulb depth planning

Planting bareroot trees

1. Dig the hole for the tree using a spade or shovel. Dig the hole two to three times as wide as the root ball and about 1 inch shallower than the height of the root ball.

2. Remove the evergreen tree from the container and examine the roots. Use your fingers to loosen any roots that are wrapping around the root ball. For a ball and burlap tree, keep the burlap secured to the root ball.

3. Place the root ball in the center of the hole. The top of the root ball should be slightly above the level of the surrounding ground. Add or remove dirt from the hole if necessary. Do not put the tree roots in direct contact with the compost

4. Back-fill the hole halfway with the soil removed from the hole. You may also amend the soil first with organic matter.

5. Finish back-filling the hole. Water again to compress the soil, adding more soil if needed. Do not place soil on top of the root ball.

6. Apply 2 to 3 inches of well rotten black crumby compost (mulch, FYM)or pine bark or leaf mold, around the tree. Keep the mulch about 3 inches from the trunk of the tree. The manure will:

• Avoid weeds from growing
• Keep moisture around the tree 
• Increase worm activity

In Ireland the best time of the year to plant evergreen trees and shrubs is from December to January.

Transplanting a tree

To transplant a well grown tree we should cut around half the roots one year, between December and January in the dormant months, and the next year, the other half so the tree does not get under shock cutting all the roots at the same time.

From September to November the sap will go down from the leaves to the roots, so the roots will keep growing even if the leaves are falling. From November to January the roots will not grow. In February the sap will start going up and will make the tree grow again.

Potted trees

The potted trees are the ones we buy in a garden center and are given to us inside a pot.

The best time of the year to plant fruit and bushes potted trees is between November and March.

The sooner the better so that the roots can start to grow before the buds do.

They have to be planted at the same depth of the pott.

If it is a potted shrub they sould bee planted between November and May, being the best April to May.

Never plant a potted plant after May.

Nursery gardens

There are different ways of planting trees, mainly:

- From the seeds
- From the original plant (cuttings, layering or suckers)
- By pollination


In the nursery gardens they grow trees that they will sell to reatilers or to the general public.

One way of growing those trees is with the seeds or from cuttings.

The seeds or the cuttings will be planted in a first bed where they will be for a year time when some roots will grow. The second year they will be moved to a different bed. This will be done year after year, during at least 10 years. The roots will grow along those years, mainly the:

• Structural roots: large roots that have undergone considerable secondary thickening and provide mechanical support to woody plants and trees.
• Fine roots: Primary roots usually <2 mm diameter that have the function of water and nutrient uptake. They are often heavily branched and support mycorrhizas. These roots may be short lived, but are replaced by the plant in an ongoing process of root 'turnover'. A plant with a healthy mycorrhizas system will give the plant 10-15 times more nutrients and water.

During that time the trees will grow as well as their roots. If they are sold, they would be sold as bareroot trees (B/r). Their prices will go up to 25€.

When the trees grow higher and the roots are bigger, the nursery garden should start balling the roots of the trees. This is done by a machine that will take the roots out from the soil, with a big amount of soil around it and will put a net around the soil and the roots. The machine will rootball and wrap the roots all together.

Those trees are bigger and are called rootball trees (r/b). They can go from 1 m of diameter in their base to 10 m or more in very mature trees. Their prices are above the 100€ and can be as high as 6,000€ if it a mature tree.

When we buy a bareroot tree it has to be planted between November and March.



When the tree is a rootball one, it will be planted between November and May.

Industrial revolution - How it affected the farming industry

In the old days, before the power of fossil energy was used in planting and cropping, the farmers used companion techniques (like the three sister planting) in order to maximise the space they had for their crops, even if that meant a loss of time.

When the fossil energy started to be used in farming, during the industrial revolution, the farmers could afford to have bigger plots as they hace the machinery to work on them faster. To plant in those big plots had a requirement, there had to be enough space for the wheels of the tractors to go in. That meant loss of space but the machinery saved a lot of time.

There is a very interesting documentary about the impact of fossil fuel in farming


Una Granja para el Futuro from Horatiux on Vimeo.

Manure (farmyard manure, compost, plant manure)

Manure is organic matter used as organic fertilizer in agriculture. Manures contribute to the fertility of the soil by adding organic matter and nutrients, such as nitrogen, that are trapped by bacteria in the soil.

There are three main classes of manures used in soil management:

Animal manures

Most animal manure is feces. Common forms of animal manure include farmyard manure (FYM) or farm slurry (liquid manure). FYM also contains plant material (often straw), which has been used as bedding for animals and has absorbed the feces and urine. Agricultural manure in liquid form, known as slurry, is produced by more intensive livestock rearing systems where concrete or slats are used, instead of straw bedding. Manure from different animals has different qualities and requires different application rates when used as fertilizer. For example horses, cattle, pigs, sheep, chickens,turkeys, rabbits, humans (sewage), and guano from seabirds and bats all have different properties. For instance, sheep manure is high in nitrogen and potash, while pig manure is relatively low in both. Horses mainly eat grass and a few weeds so horse manure can contain grass and weed seeds, as horses do not digest seeds the way that cattle do. Chicken litter, coming from a bird, is very concentrated in nitrogen and protein and is prized for both properties.

Animal manures may be adulterated or contaminated with other animal products, such as wool (shoddy and other hair), feathers, blood, and bone. Livestock feed can be mixed with the manure due to spillage. For example, chickens are often fed meat and bone meal, an animal product, which can end up becoming mixed with chicken litter.

Compost

Compost is the decomposed remnants of organic materials – usually of plant origin, but often including some animal dung or bedding.

Plant manures

Green manures are crops grown for the express purpose of plowing them in, thus increasing fertility through the incorporation of nutrients and organic matter into the soil. Leguminous plants such as clover are often used for this, as they fix nitrogen using Rhizobia bacteria in specialized nodes in the root structure.

Other types of plant matter used as manure include the contents of the rumens of slaughtered ruminants, spent hops (left over from brewing beer) and seaweed.

Crop rotation

If we have a garden of a certain size we would be able to establish a crop rotation system that will help to fight the pests and to improve the use of nutrients by different groups of plants.

If we have enough space to organize 5 beds, we will establish a 4 year rotation.

1. Legumes: They are good nitrogen fixes. They do not like fresh lime
2. Brassicas: They are heave nitrogen user. They do not like lime
3. Alliums: They have shallow roots. If they grow in the same area for more than two years the fungi white-rot will appear and ruin the crop
4. Root/tubers: They are heavy fresh manure users (high potasium and sodium). They have deep roots (potatoes, tomatoes... never plant potatoes and tomatoes together as they will spread a disease from on to the other)
5. Permanent crops (crops that will not rotate every year) 

• Artichoke
• Rhubarb
• Aspharagus
• Strawberries
• Currants
• Apple... 

 In our rotation plan we have to consider rotating also between the indoor and outdoor crops.

Flowering plants

They are divided into 250 groups. In each of the groups there are plants that are edible and some that are poisonous. Each group has similar flowers. Each of the groups would also have specific diseases that is why the crop rotation is needed, so diseases do not get used to the plants of that group.

The most important families are:

• Brassicas (they have buds;  cabbage, cauliflower, broccoli, Brussel sprouts...)
• Legumes-Fabaceae or Leguminosae (they have a pod that contains seeds;  alfalfa, clover, peas, beans, lentils, lupins, mesquite, carob, soybeans, peanuts...)
• Apiaceae (carrot family, root crops; angelica, anise, arracacha, asafoetida, caraway, carrot, celery, Centella asiatica, chervil, cicely, coriander/cilantro, cumin, dill..)
• Curcurbit-Cucurbitaceae (cucumber family;  cucumber, pumpkins, luffas, and watermelons...)
• Solanum (Most parts of the plants, especially the green parts and unripe fruit, are poisonous to humans (although not necessarily to other animals), but many species in the genus bear some edible parts, such as fruits, leaves, or tubers. Several species are cultivated, including three globally important food crops:

1. Tomato, S. lycopersicum (they do not grow tubers ant the tomatoes are edible)
2. Potato, S. tuberosum (the tomatoe/berries that grow in the potato plant are poisonous)
3. Eggplant, S. melongena (the tomatoes (aubergines i.e.) are edible)

• Rosaceae (rose family, the seeds look quite similar in all of them;  apples, apricots, plums, cherries, peaches, pears,raspberries, strawberries, rose...)
• Polygonaceae (leaves are somehow triangular, the seeds are pyramidal; rhubarb, buckwheat, sorrels, ...)
• Asteraceae - Thistle (aster means star in greek, its name its related to the inflorescence star form; daisies, fleabane, chrysanthemums, dahlias, zinnias, globe artichoke, sowthistle, hawkweed, dandelion...)
• Amaryllidaceae - Allium (bulbous flowering plant; onion, garlic, leeks, tulips, lily, ....)
• Poaceae/Gramineae (grass family; wheat, ryegrass, oats, bamboos, thatch, ...)
• Rubiaceae (coffee family; coffee, quinine, ...)

Groups of plants

Moss & Liquens	Ferns	Conifers	Flowering plants
Non woody. First plants to colonize Earth. An area where there are moss & lichens it is a clean area. The least moss and liquens there are, the most polluted its the area.	They reproduce by spores. Unlike mosses, they have xylem and phloem (making them vascular plants). They have stems, leaves, and roots like other vascular plants. Ferns reproduce via spores and have neither seeds nor flowers.	Plants that produce cones. They tolerate cold thanks to the resine. Pinophytes are gymnosperms. They are cone-bearing seed plants with vascular tissue; all extant conifers are woody plants, the great majority being trees with just a few being shrubs.	They propagate by flowers. They evolved when insects appeared. They were the last group to appear in Earth.

Oaks

An oak is a tree or shrub in the genus Quercus, of which about 600 species exist.  The genus is native to the Northern Hemisphere, and includes deciduous and evergreen species extending from cool temperate to tropical latitudes in Asia and the Americas.

Oaks have spirally arranged leaves, with lobed margins in many species; some have serrated leaves or entire leaves with smooth margins. Many deciduous species are marcescent, not dropping dead leaves until spring. The flowers are catkins, produced in spring. The fruit is a nut called an acorn, borne in a cup-like structure known as a cupule; each acorn contains one seed (rarely two or three) and takes 6–18 months to mature, depending on species.

In Ireland the most common oaks are:

Sessile - Quercus Petraea

Peduncular Oak (Irish) - Quercus robus

The oaks are one of the most valuable biodiversity plants. They can support over 300 species of wild life (insects and birds mainly).

Pines can also support a handful.