Facebook
X (Twitter)
Reddit
Pinterest
Tumblr
LinkedInPosts Tagged: planting
Planting Avocados
It seems like the simplest thing is the hardest. Recently, I was called out to evaluate why newly planted trees were failing at two sites and they both had a common problem. In one case, the trees had been planted too deeply at the beginning. At another, a large amount of planting amendment had been incorporated, and over a year's time, the trees had settled, so that they too had their graft unions covered with soil. In the latter case, the trees' unions were 4-8 inches below grade. It seems appropriate to review basic planting practices. In the best-case scenario, trees are planted from February to May, but depending on the area, they can be planted at other times, as well. So, I just got a call about planting, so it's probably time for a refresher.
Often times the grower harkens to the old adage: “dig a $5 hole for a 50-cent plant.” And so a lot of time and money and energy are put into that hole. Nothing costs $5 anymore. Trees cost closer to $50, so there might be a greater urge to do it all right. So the first thing first is forget the planting mix and those mycorrhizal inoculums. They either don't work or they might just damage your expensive tree.
Adding organic matter to a planting hole appears to be a promising step towards achieving that five-dollar hole. It seems logical that steer manure, peat moss, compost, etc. would improve poor soils by increasing aeration, nutritional value, and water holding capacity. And it does - in the immediate vicinity of the planting hole. Eventually, amended planting holes will have negative consequences to plant health.
The initial results are positive; roots grow vigorously in this ideal environment as long as irrigation is provided. But what happens when these roots encounter the interface between the planting hole and the native soil? Native soil contains fewer available nutrients, is more finely textured and is less aerated. Roots react much in the same way as they do in containers: they circle the edge of the interface and grow back into that more hospitable environment of the planting hole. The roots do not establish in the native soil, eventually resulting in reduced growth rates.
Soil water movement is problematic as well. Amended backfill has markedly different characteristics than surrounding native soil; it is more porous and water will wick away to the finer-textured native soil. In the summer, moisture within the planting hole will be depleted by the plant but not replaced by water held more tightly in the native soil. When irrigating, water will move quickly through the amended soil only to be held back by the more slowly draining native soil. The resulting bathtub effect, where water accumulates in the planting hole, floods the roots and eventually kills the plant.
Finally, all organic material eventually decomposes. If you've incorporated organic matter, within a few years that organic matter will have become ash and the bulk has turned into carbon dioxide. The soil will have settled and if you have followed the rule of thumb of 25% by volume, the trunk stem probably will have sunk below grade and the bud union will be buried. The buried union only exacerbates the flooding problem during irrigation or wet conditions. This was the problem that I went out to see.
Basic planting steps
1) Dig a hole somewhat wider, but no deeper than the sleeve that the tree comes in. Making the hole wider (18 inches) allows room to manipulate the tree by hand and remove the sleeve once it is in the hole. Making the hole deeper than the sleeve allows for soil to accumulate around the graft union. Even if the hole is backfilled to the “appropriate” depth, because of subsidence of the loose earth, the tree can become buried. Do not put gravel in the bottom of the hole. This is commonly thought to improve drainage. It does not, it makes it worse.
2) Gently tamp loose earth around the tree. Do not back fill with a planting mix. This creates a textural discontinuity which interferes with water movement both to and anyway from the tree. The fill soil should be free of clods to avoid air gaps and poor contact between roots and soil. Do not cover the root ball with soil; the irrigation water needs to come into direct contact with the root ball.
3) The trees should be watered as soon as is practical after planting.
4) Using drip irrigation the, the emitter should be near the trunk, so that water goes directly onto the root ball. Shrinking and swelling of the polyethylene tubing can move the emitter off the ball.
5) After about 4-6 months the drip emitters can be moved from the trunk to 6-8 inches from the tree. Moving the emitters avoids keeping the trunks wet and reduces the likelihood of crown rot.
6) In most situations, newly planted trees should be irrigated every 5-10 days with 2-5 gallons of water for the first 2-4 months until the roots get out into the bulk soil. Depending on what the weather is like, they still might require frequent irrigations, because the rooted volume holding water is still small. After the first year in the ground, another dripper can be installed on the opposite side of the tree. As the tree grows the number of drippers should be increased or the system converted to fan or microsprinklers.
And in the case of mycorrhizae, they are wonderful. They are nature's gift to all of us. They aid plants in their uptake of nutrients, improve plant health and may actively transmit information from one plant to another. They are a diverse range of fungi associated with plant roots and are everywhere – even Antarctica. And that's the point, introducing them to the planting is not going to help. They are there already, a sea of them. Putting a few nursery-grown spores into a planting hole when there are already highly adapted fungi present just does not happen easily. So not using a planting mix and not adding mycorrhizal inoculum is going to make that hole a little bit cheaper.
In root rot conditions
Planting in ground that has had root rot can add some new steps to the planting process. On relatively flat ground (
The key to root rot has always been dependent on irrigation management. There is nothing more important than getting the right amount on at the right time. If you are doing interplanting into an existing orchard where trees have died, it is imperative that the new trees be put on their separate irrigation line so that they can be irrigated according to their needs. Simply putting a smaller emitter on the young trees compared to the older trees means that they will still be irrigated on a cycle that is not optimum for their survival. It doesn't matter if you are using clonals; they will die just as easily with poor water management as a seedling.
Check out the pictorial guide to proper tree planting
avocado planted
Planting Avocados and lotsa other trees
Planting Avocados
It seems like the simplest thing is the hardest. Recently, I was called out to evaluate why newly planted trees were failing at two sites and they both had a common problem. In one case, the trees had been planted too deeply at the beginning. At another, a large amount of planting amendment had been incorporated, and over a year's time, the trees had settled, so that they too had their graft unions covered with soil. In the latter case, the trees' unions were 4-8 inches below grade. It seems appropriate to review basic planting practices. In the best-case scenario, trees are planted from February to May, but depending on the area, they can be planted at other times, as well. So, I just got a call about planting, so it's probably time for a refresher.
Often times the grower harkens to the old adage: “dig a $5 hole for a 50-cent plant.” And so a lot of time and money and energy are put into that hole. Nothing costs $5 anymore. Trees cost closer to $50, so there might be a greater urge to do it all right. So the first thing first is forget the planting mix and those mycorrhizal inoculums. They either don't work or they might just damage your expensive tree.
Adding organic matter to a planting hole appears to be a promising step towards achieving that five-dollar hole. It seems logical that steer manure, peat moss, compost, etc. would improve poor soils by increasing aeration, nutritional value, and water holding capacity. And it does - in the immediate vicinity of the planting hole. Eventually, amended planting holes will have negative consequences to plant health.
The initial results are positive; roots grow vigorously in this ideal environment as long as irrigation is provided. But what happens when these roots encounter the interface between the planting hole and the native soil? Native soil contains fewer available nutrients, is more finely textured and is less aerated. Roots react much in the same way as they do in containers: they circle the edge of the interface and grow back into that more hospitable environment of the planting hole. The roots do not establish in the native soil, eventually resulting in reduced growth rates.
Soil water movement is problematic as well. Amended backfill has markedly different characteristics than surrounding native soil; it is more porous and water will wick away to the finer-textured native soil. In the summer, moisture within the planting hole will be depleted by the plant but not replaced by water held more tightly in the native soil. When irrigating, water will move quickly through the amended soil only to be held back by the more slowly draining native soil. The resulting bathtub effect, where water accumulates in the planting hole, floods the roots and eventually kills the plant.
Finally, all organic material eventually decomposes. If you've incorporated organic matter, within a few years that organic matter will have become ash and the bulk has turned into carbon dioxide. The soil will have settled and if you have followed the rule of thumb of 25% by volume, the trunk stem probably will have sunk below grade and the bud union will be buried. The buried union only exacerbates the flooding problem during irrigation or wet conditions. This was the problem that I went out to see.
Basic planting steps
1) Dig a hole somewhat wider, but no deeper than the sleeve that the tree comes in. Making the hole wider (18 inches) allows room to manipulate the tree by hand and remove the sleeve once it is in the hole. Making the hole deeper than the sleeve allows for soil to accumulate around the graft union. Even if the hole is backfilled to the “appropriate” depth, because of subsidence of the loose earth, the tree can become buried. Do not put gravel in the bottom of the hole. This is commonly thought to improve drainage. It does not, it makes it worse.
2) Gently tamp loose earth around the tree. Do not back fill with a planting mix. This creates a textural discontinuity which interferes with water movement both to and anyway from the tree. The fill soil should be free of clods to avoid air gaps and poor contact between roots and soil. Do not cover the root ball with soil; the irrigation water needs to come into direct contact with the root ball.
3) The trees should be watered as soon as is practical after planting.
4) Using drip irrigation the, the emitter should be near the trunk, so that water goes directly onto the root ball. Shrinking and swelling of the polyethylene tubing can move the emitter off the ball.
5) After about 4-6 months the drip emitters can be moved from the trunk to 6-8 inches from the tree. Moving the emitters avoids keeping the trunks wet and reduces the likelihood of crown rot.
6) In most situations, newly planted trees should be irrigated every 5-10 days with 2-5 gallons of water for the first 2-4 months until the roots get out into the bulk soil. Depending on what the weather is like, they still might require frequent irrigations, because the rooted volume holding water is still small. After the first year in the ground, another dripper can be installed on the opposite side of the tree. As the tree grows the number of drippers should be increased or the system converted to fan or microsprinklers.
And in the case of mycorrhizae, they are wonderful. They are nature's gift to all of us. They aid plants in their uptake of nutrients, improve plant health and may actively transmit information from one plant to another. They are a diverse range of fungi associated with plant roots and are everywhere – even Antarctica. And that's the point, introducing them to the planting is not going to help. They are there already, a sea of them. Putting a few nursery-grown spores into a planting hole when there are already highly adapted fungi present just does not happen easily. So not using a planting mix and not adding mycorrhizal inoculum is going to make that hole a little bit cheaper.
In root rot conditions
Planting in ground that has had root rot can add some new steps to the planting process. On relatively flat ground (<15 degree slope) trees will benefit from being planted on a berm or mound. This creates better aeration and drainage for the roots. It also means that the trees tend to dry out faster, so more frequent irrigation may be necessary. Where machinery can be employed, creating berms is usually less expensive. Surrounding soil should scraped to the planting site, and little incorporated with the soil surface where the berm or mound is to be built. In bringing surrounding native soil to the planting site, it is important that an interface between the imported soil and the soil surface is not created. Just mounding a different soil on top of a surface alters water flow through the mound into the bulk soil. The berms can be built 1.5 to 2 feet high with a 4:1 slope. The raised planting position should be irrigated to settle the soil. The soil should then be allowed to dry out prior to planting to avoid mucky soil. Only clonal rootstocks should be replanted into root rot soil. Applying gypsum (15 pounds per tree), a thick layer of mulch around the base of the tree (3-6 inches deep, but not immediately on the stem of the tree) and finally application of fungicides will help. Application on the berm or mound also protects the soil from eroding away with rains.
The key to root rot has always been dependent on irrigation management. There is nothing more important than getting the right amount on at the right time. If you are doing interplanting into an existing orchard where trees have died, it is imperative that the new trees be put on their separate irrigation line so that they can be irrigated according to their needs. Simply putting a smaller emitter on the young trees compared to the older trees means that they will still be irrigated on a cycle that is not optimum for their survival. It doesn't matter if you are using clonals; they will die just as easily with poor water management as a seedling.
The following is a pictorial guide to proper tree planting ( click on "ATTACHED FILES" planting holes.
planting holes
young avocacdo tree
Avocados & Other Trees Blog
It's so nice to be able to find a way to rapidly answer homeowner questions. Once one questions has been addressed, invariably another one pops up. There are mysteries to plants and they can go on and on forever. The University of California Cooperative Extension has locally trained volunteers to answer the questions that local homeowners are going to ask about local plant problems. You can find Master Gardener contacts by going to the map to find a local office and the local MG Helpline: http://ceventura.ucanr.edu/Offices/
Recently I got an email from a homeowner that had a burning question about the name of an avocado found in a picture. That one question lead to another and to another and eventually to how to plant a tree in a heavy clay soil. i was going through explanations, and suddenly remembered a website put together by Greg Alder with photo steps going through the whole process: http://gregalder.com/yardposts/how-to-plant-and-stake-an-avocado-tree/
After passing that link on to the homeowner, I havent had any more questions about planting avocados. The site does the trick.
So if you are looking for more answers about avocados, the Annual Meeting of the CA Avocado Society is October 4 - next month. Come on the tour and see how it's done:https://californiaavocadosociety.org/annual-meeting.html
Filling a planting hole to see if water drains well enough before planting an avocado. A great photo from the blog.
filling a hole
Tree Staking Myths
"Trees should be firmly staked at planting"
MYTH!!!!!!!!!!!!!!! Read on:
Chalker-Scott, L. , Extension Specialist And Associate Professor, Washington State University
Downer, A.J., Farm Advisor, University of California
Nursery-grown shade trees are often rigidly staked to prevent blowdown and damage during cultivation. In some cases, trees are pruned to a long, untapered standard with a bushy top that requires a tight stake to hold it up. Nurseries often remove side branches from the young trunk and while this creates the illusion of a small tree, the practice actually inhibits the development of taper in the trunk (Harris, 1984; Neel and Harris, 1971). Trees without taper will not stand without staking. Poor culture of ornamental trees in nurseries necessitates staking once trees are planted into landscapes because they do not have the structural development in their trunks to stand on their own. Due to these cultivation errors, landscape installers frequently keep the nursery stake and add more stakes to firmly secure the tree in place and further prevent its movement in the landscape.
Staking takes three basic forms: rigid staking, guying, and anchoring. All methods of staking reduce development of taper, increase height growth, and decrease caliper of the developing tree relative to unstaked trees (Figure 7). Moreover, improper staking can result in increased tree breakage either during the staking period or after staking is removed (Figure 8a-b) (Thacker et al., 2018).
Decades ago, researchers discovered that movement of the trunk and branches is necessary for the development of trunk taper (Neel and Harris, 1971). Trees grown in a growth chamber without movement did not develop taper and instead grew taller, while trees in an identical chamber that were hand shaken each day developed significant taper and remained shorter.
Until trees are established in landscapes they may require some staking. In areas of high wind, guying (which involves cables staked to the ground) gives the greatest protection against main stem breakage or blowover (Alvey et al., 2009). Whatever system is used, any such hardware should be removed as soon as the tree can stand on its own:
- The traditional two stakes and ties system is the least harmful to trees staked in landscapes.
- Staking should be low and loose to allow trunk taper to develop naturally.
- Remove all staking material as soon as possible.
If a tree is not established after a year of staking, it is unlikely to ever establish
Read on:
avocado lindcove
Water Magic and How Best to Irrigate New Container-Grown Trees in the Field
This article first appeared in Sacramento Valley Orchard Source
Missing the Target: Why you Should Irrigate Potted Trees Directly onto Potting Media
or
Why Emitters Should be Placed on the Root Ball at Planting
Dani Lightle, UCCE Orchards Advisor, Glenn Butte & Tehama Counties
N.B. potted trees are standard commercial container grown citrus and avocado trees
Generally, when I am working with growers on a problem related to potted-tree establishment, the cause is lack of water movement into the potted media, creating tree stress. This results from the difference in soil particle size at the boundary between the orchard soil and the tree's potting soil. When you plant a potted tree in your orchard, it has a substrate – some mix of peat and vermiculite – that is very different than your soil type. The change in texture and pore size inhibits water movement from the surrounding soil into the potting media. As a result, Irrigation water applied outside the potted soil media isn't getting to the roots.
The sequence of photos in Figure 1 demonstrates this phenomenon. I set up a mock orchard condition with soil (Tehama series silty loam) next to a potted tree (potting soil) in a ½ inch wide frame. I then slowly added water to match the soil infiltration rate, similar to a drip emitter, approximately 4 inches away from the potting soil in the ‘orchard' soil.
You will see that the water does not move into the potting soil (Figure 1C & D). Two forces – gravitational pull and capillary action – move water downward and laterally in the soil. Since the potting soil is not below the orchard soil, gravity does not move water into the potting soil. Capillary action is not strong enough to move water into the potting soil because the difference in pore size is too great. So, irrigation water goes where it can easily flow – downwards and laterally into dry, native soil but not into the potting soil. More water does not solve the problem, it will just move past your newly planted trees and wet more native soil.
For about the first month of growth, irrigation emitters should be located at the base of the potted tree to ensure the potting medium receives water. Frequently check to ensure that the potting soil stays wet – not the soil somewhere else in the tree row or mound – before, after, and between irrigation sets. The best way to do this is with a small trowel and your hands. Water will need to be applied at the base of the tree until the tree roots grow beyond the potting soil and into your orchard's native soil. The time required for this to happen will vary depending on factors such as temperature, but it should take roughly a month.
Figure 1. This sequence of photos shows the movement of water applied to Tehama series silty-loam soil. Water was applied at the blue arrow, approximately 4 inches from the potting soil. Total elapsed time was 51 minutes. Water moved downwards and laterally but did not cross the boundary into the potting soil.
water movement all together
irrigATING CITRUS
