Move Sago Palm to Bigger Area this Fall

Q. I have a healthy sago that is outgrowing its space rapidly. When is the best time to relocate it? Is relocation successful usually? It is such a nice plant that I hate to risk endangering its life.

 

A. You would move it this fall, some time between the end of September and mid-October, or next spring. You should not have a problem relocating it. I would not put it any closer than five feet from anything you don't want it to touch or invade like a sidewalk or wall.

            Hopefully you will put it on the north or east side of a building or in a spot with a little wind and sun protection and not use rock mulch around it. Pre-dig your hole for the plant. Make sure the hole and soil for replanting are prepared well with compost and a starter fertilizer high in phosphorus.

            Remove the bottom tier of fronds from the trunk. I would leave only the fronds which are at about 45 degrees from horizontal and the inner fronds. Remove the older ones that are below this point. Bend the remaining fronds up around the central bud and wrap some twine around them to hold them together if they are pokey.

            Take as much of the root system you can when you move it. Cut deeply with your shovel all the way around the plant about a foot to 18 inches from the trunk. Cut the roots in a complete circle all the way around the plant at least twice making sure all the roots are cut. Cut as many of the roots as deeply as you can.

            On the third trip around the plant cut in the same spots but push down on your shovel handle and begin leveraging the palm upwards. Move to a new spot and repeat it until you have gone around the plant, leveraging and lifting, the third and fourth time with your shovel.

            The plant should almost be free now or, if you are in luck, it can be lifted by the fronds. If not, then push the plant on its side and cut any remaining roots with your hand shears to free it. Tying the fronds up should make it easier to do all this and move it.

            Move and orient it so it looks nice. Don't worry about orienting it the same compass direction as it was before. Backfill around the plant and run water in the hole at the same time you are backfilling to remove any air pockets.

            Plant it the same depth as it was in its original hole, no higher or deeper. Put a small moat around the plant to contain water from the hose when hand watering. You can drip irrigate the plant but still hand water it for the next 2 to 3 weeks, filling the moat each time. Untie it and release the fronds.

            In the spring, remove the bottom layer of fronds at the base of the crown just leaving juvenile fronds that are upright. You will see new growth from the center and it should regrow and fill the canopy in the first year.

Brown Spots in Lawn Probably Summer Patch Disease

Q. I believe I am dealing with some fungal outbreak on my new lawn. About a month ago I started to see faint circles of stressed lawn. They range from 24 to easily 48 inches wide. They are certainly not dog urine spots. I know the difference.  Also confident it's not a watering problem. All spring and early summer the lawn has been healthy and looking great. But now these circles are appearing everywhere.  Am I going to need to just throw in the towel and start over?

A. This is most likely a fungal disease called Summer Patch. Buy a lawn fungicide at your local nursery that either says it controls Summer Patch or (less likely) as well as necrotic ring spot disease.

            Fungicides are primarily preventive so making an application now during this hot weather will arrest the disease from going any further but not reverse the damage done. Look for a turfgrass fungicide that states it will control Summer Patch disease, Fusarium diseases or "frog eye" on the label. Follow the label precisely in application. If the label states it also controls Necrotic Ring Spot as well, so much the better.

            This is a “hot weather” disease of lawns and favors soils that stay wet and don't drain readily. Since this is a hot weather disease, you can always expect it to occur when temperatures are rising and become particularly aggressive during the "summer monsoon" season where relative humidity takes a bump along with high temperatures.

            Next year anticipate an outbreak to start in June and make your preventive fungicide application then or when you start to see those “faint circles” appearing.

            I would aerate the soil now as well. You can use a simple hand aerator that you can buy at the nursery or you can rent a power aerator from a local rental company. Don’t use the shoes with the spikes on the bottom. They are a gimmick.

            Remember this problem area in the future. Prior to the onset of hot weather, aerate to improve water drainage from the area around grass roots. Mow the lawn at its minimum acceptable height (usually 1 1/2 inch for tall fescue) to improve air circulation in the stand of grass.

            Avoid excessive applications of nitrogen fertilizers but keep the lawn fertilized "adequately". This will usually mean about half the label rate mentioned for lawns on the fertilizer bag.

            This is particularly true if you are mulching the clippings back into the lawn with a mulching mower. Returning the clippings to the lawn with the mulching mower has no bearing on this disease in a lawn.

V Shaped Cross Marks on Tomato

Q. I have 'Vee’ shaped cross marks on my tomatoes (especially from Celebrity tomato) starting from the stem and reaching out and down about 1/4 the side.  I always thought these were from lack of water but we try to give all extra water by letting the hose end flood each for 5-10 minutes at least once a day in addition to drip irrigation at 1am, 3am and 5am for 6 minutes each.

A. I think you either are explaining either “catfacing” or “cracking” of the fruit. This is a surprise since Celebrity is known for its lack of both and was developed with one of its intentions to reduce cracking. Some of this type of prevention is by picking the right variety (Celebrity should be one!) for growing and some is garden management.

Fruit cracking on Caspian Pink heirloom tomato

            Two things I can think of contribute to cracking. Catfacing is a different issue. I gave you a couple of links to look at to determine what  you might have. Cracking can be down the side from the stem or around the circumference of the fruit.

            Two things important in cracking are how well the tomato skin will expand without breaking (cracking) and soil moisture. Try to water in the early moring hours several hours before it gets hot.

            Secondly, cover the soil with a light mulch like straw to help slow down the loss of water from the soil.

Radial cracks on Caspian Pink

            The last thing is something that I think most people neglect. Good soil preparation at the time of planting. If the soil is pretty heavy and not “fluffy” or what we call “crumby” (like bread crumbs kind of crumby or a cake-like texture) the roots of the plant will be forced to grow close to the soil surface.

            If the majority of the roots are close to the surface where water is lost quickly during the heat the plant will go into water stress (drought) very soon after an irrigation. If the soil is prepared well so that it has a “crumby” structure then plant roots are distributed through the soil so that it can take up more water before it becomes water stressed.

            Going from water stress to water abundance leads to expansion of the fruit and can lead to splitting. Having enough foliage covering the fruit can also reduce cracking so good canopy coverage of the fruit is important.

Topdressing with straw mulch

            So make sure you soil is well prepared to a depth of at least 12 inches when planting or plant in a raised bed with well prepared soil. Secondly, apply a surface mulch no later than when the fruit begins to set.

            Third, water at the beginning of the day before it gets hot to reduce water stress. Fourth, make sure the plants are healthy and have good foliage covering the fruit. This means the right fertilizer at the time of planting and followup monthly fertilizer applications when you see fruit setting and you are harvesting. These are small applications of fertilizer or lightly foliar feed in the early morning hours.

How Safe is Wood for Smoking if Pesticides Were Used?

Q. I have searched online for an answer to the question, is using wood from a commercial orchard safe to use for smoking meats? I live in Tulsa, OK and have several local orchards that use pesticides, fungicides, etc. in their operation. I found your contact info on a flyer online. I don't know whether or not you use any of these but i figured you might have an answer or direction to the question. I would appreciate your input very much.

A. I think this is a matter of opinion. Some people would be adamantly opposed to using wood unless the tree was grown “organically”.

            Having a background in pesticides and the use of pesticides in orchards I would not be afraid of using wood from such an orchard provided it had been applied several months prior to it being cut. Most pesticides don’t have a particularly long life once they have been hit by the environment (sunlight, air, rain, etc.)

            What residue is left is on the surface of the trees (bark) and not “inside” the tree. Most pesticides that end up inside the plant are called “systemic” and almost none are allowed for use in fruit and vegetable production. This is because it is thought that this pesticide would be moved around or translocated to the fruit and vegetables we eat.

            If they were used they would be “translocated” through the layers of living wood just under the bark of the tree. This is the pathyway that “systemic” pesticides would take to allow it to move around inside the tree.

            We have had similar questions about smoking wood where the bark  has been “painted” with latex paint for sunburn protection. I have told people in the past when they had some concerns to remove or burn off the outside bark of the wood with some high temperatures and then turn down the temperature and put in your food for smoking.

            If you are using wood with no bark on the outside then you don’t have to do anything. The “wood” of the tree is “dead” and an accumulation of the tissue which was alive previously and transported stuff inside the tree.

Date Palm Not Producing Fruit

Q.  I have a 5-year-old date palm that this year for the first time had a wonderful display of fruit. It is a Medjool date palm that I grew from seed. The fruits are at least 1.5 in long and round. But now they are falling off in great numbers. I thought that birds were on them thinking they were grapes which I have nearby. But I have covered the Medjool dates with cloth and still they are all almost gone. Another date palm nearby, a Deglet Noor (8 years old) has a great fruit set but just very few drops. Could it be that my Medjool has not been pollenized?

Flower spikes coming from Canary Island Date Palm

A. Exactly right. The fruits dropping have not been pollinated. No, or poor pollination, can happen for a number of reasons but I am guessing the reason in this case is because there was no male pollinator in the area with open flowers.

            I wish it was easier but what can you can do, outside of planting a male Medjool palm, is create a source of pollen for your female tree and hand pollinate the female flower cluster when they open.

            You will have to find a male Medjool date palm (flowers will be produced at the same time as the female Medjool but not produce any fruit at all) that is low enough to the ground for you to reach.

Flowers not yest open on CI date palm

            When the male tree is producing its floral spike next early summer and near flowering, prune several spikes out and put them in a clean bucket of water. Move the bucket close to the base of your palm and let the flowers open. Replace the water daily with clean water.

            When the flowers are open, shake the male flower spike and flowers pretty hard against the female spike attached to the tree. Replace the male flower spike in the bucket of water and repeat over the next couple of days as more and more flowers open.  

 

            Alternatively, you can tie the male flower spike to the female flower spike and cover with a bag. Beat the bag pretty hard and leave the bag in place for a couple of days and then remove.

Cactus Dead or Near Dead in Summer

Q. Our cactus has started to die from the top down. We lost our first one in May, before the summer heat even started.  Do you have any idea why this is happening?  We were watering, with bubblers, three times a week, for about 5 minutes. We increased that when they started to die, but it did no good. Any information will be appreciated. 

Readers cactus dead or with severe damage

A. Wow, judging from the pictures you do have a problem. The plant looks dead from top to bottom. This looks like one of the Cereus or night-blooming cacti, a pitaya type.

            When did you see this happening? This looks very similar to freeze damage from the winter but if you are just seeing this now then of course it is not. Another possibility is root rot if watering too often and not giving it a break of dry soil between waterings.

            Three times a week is going to be excessive for this plant and may be the problem. The plant would prefer a large amount of water and then long times between waterings, much like rainfall in dry climates.

Another view.

            But bottom line the soil needs to dry thoroughly between waterings to prevent root rots. When planting, make sure the soil is amended with some real good stuff at planting. Cacti can survive poor soils better than many plants but also perform better with an enriched environment provided the soil drains water freely and dries between irrigations.

Should I Plant Lemons or Limes?

Q. Will either dwarf lime or lemon trees do well here? We consider pots but our patio faces the west and gets very hot. We have a small space for pots in the front yard which faces east. Any suggestions?

 

A. The principle limitation for citrus here is winter cold. Cold tolerance in citrus generally follows this progression of tolerance from the most hardy to least goes something like this: (most) kumquat, Meyer’s lemon, grapefruit, Mandarin or Satsuma orange, navel orange and lime (least).

Eureka lemon tree in Las Vegas. Fruit still immature.

            Once you get to navel orange the rest will not handle any freezing. You should locate citrus in the part of the yard that is the warmest in the winter and protected from cold winter winds.

            If you like lemons, Meyer’s is a good choice and very popular in Las Vegas even though it is not a true lemon. I would put limes only in much protected locations.

Water Your Trees With a Hose Instead of Drip Works!

Q. How often should I water my California pepper tree, Mediteranean fan palm and my Canary Island date palm These are the only trees I have on my property. I hand water them. How often should I be watering them with the extreme temps we are having?

A. We have to take into consideration both how often and how much to water. The “how often” will be the same. Or in other words all the trees you mentioned will all be watered with about the same frequency.

            How much is also going to be about the same except for their size. The larger the canopy, or size of the tree, the more water it uses. This time of year, with temperatures in the triple digits, I would be watering two to three times a week depending on your soil and if you have mulch on the soil surface. Generally speaking, a layer of mulch will save you about one extra day that you do not have to water.

            Make sure, though, that you are leaving at least one day dry between irrigations. Watering too often and keeping the soil sopping wet will lead to roots rotting. If soil is piled against the trunk and kept wet, the trunk will rot.

            I would suggest that you put a “moat”, depression or basin around the trees to contain the irrigation water from your hose. This depression, if it is maintained so that it stays at the same capacity around the tree, will guarantee that the trees get the right amount of water each time.

Irrigation basin for watering with surface mulch applied

 

          The depression can be a moat that is a wide donut or trench around the plants. This can be a small one when first planted but must be increased in capacity as the plant gets bigger. The depression or donut should be 3 to 4 inches deep and wide enough to contain 5 to 10 gallons of water when young and expanded to contain up to 40 gallons when thre tree is larger in a few years.

            The only exception to this is the palm. Many palms have the same size canopy when they are five feet tall as when they are 20 feet tall. With the same sized canopy later in life, they will use the same or similar amount of water. So for these types of palms, one sized depression should be fine during its lifetime.

            There have been criticisms with this type of watering that letting water surround the trunk might cause the trunk to “rot” or become diseased. Watering with a moat or donut around the tree is far more likely to cause problems if wet soil is left in contact with the trunk.

Water against the trunks of trees when irrigating does not kill the tree UNLESS you do it too
frequently and keep the trunk wet. In many cases it is worse to have wet soil against the trunk.

            For this reason I prefer a depression around the tree rather than a “moat” or “donut” around it. As long as the trunk dries for 24 hourse after an irrigation, trunk or collar rot will not be a problem. It WILL be a problem, however, if wet soil is left in contact with the trunk. So don’t pile soil against the trunk that will get and stay wet between irrigations.

            These depressions should be gentle, sloping depressions and not deep trenches from World War I!. When constructing these depressions, I like to start on the “high side” of the tree and use a common hoe to construct it. Pull soil to the low side when you create the depression so you can “berm” up on the low side and contain the water. The bottom of the depression should be as flat as possible.

            Start creating your depression and run your hose with a gentle amount of water coming out. Craft your depression or moat so that the water begins to fill this moat as you are constructing it. Running the water will help you get the bottom of the moat level and fill the basin around the tree without moving the hose.

            Buy one of those inexpensive hose water timers that you turn on like a kitchen timer. It will turn off the water depending on the number of minutes you dial in. It will save you water in the long run because, if you are like me, we tend to forget what’s cooking if we don’t use a timer.

            Don’t just dig a trench and fill it with water when you are done. It will never be level unless you dig it at the same time you are running the water. This type of irrigation is called “basin irrigation”, a type of flood irrigation but you are using a hose. Fill this basin twice when you water. The basin can also be used for applying fertilizer.

Help! All My Shrubs Died! Steps for the Brown Thumber

Q. I have been having problems with my shrubs and plants growing this year and am hoping you can help. I started planting in April, I planted mostly evergreen shrubs because I like to look at the green all year around. I used top soil to plant them, and they have all died. Is there something I am doing wrong? Can you tell me what evergreens I should plant(ones that stay green all year around), what month I should plant them and exactly how I should plant them? What soil to use? And how often I should water them? I don't have a watering system so I water them myself. I aprreciate it so much and am hopeful you can help me. Thank you.

 

 

A. You have asked for a whole book worth of information. It is not something that I could do or explain to you easily. Any planting you want to do now that is summer should be delayed until the end of September to the middle of October, no later. Dig and prepare your holes BEFORE you buy your plants.

Start with trees first. This is a “window shopping” trip. Don’t buy them yet. You will leave with something, but not the trees. When you leave the nursery you should be leaving with the plant, the phosphorus fertilizer, a bag of soil amendment for each plant. Stake the trees. If the tree is really small and you plant it correctly, you may not need to stake it. Shop for trees that will shade the south and west side of your home for some break from the summer heat. For these two spots I would pick trees that don’t get more than 20 to 30 feet tall for a one story house and they should drop their leaves in the fall. Leaf drop in the late fall will allow some winter sun in that can warm the house and reduce you heating costs. Do not plant these trees any closer to the house or themselves than half of their mature height.

Once you have found the trees you want, then go home and dig the holes and take all the soil prepartion stuff with you. All these plants will need to have soil improvement before you plant them. This means you will have to dig each hole about five times wider than the container it comes in. It should be the depth of the container, not much deeper.

Next, remove rocks larger than a golf ball from the soil taken from the hole. When this is done you will mix a “planter mix” soil amendment with the soil removed from the hole. I would also add a phosphorus fertilizer to this soil as well, something like 0-46-0 or similar. About two handfuls of this for each hole will be enough for shrubs and small trees. This is all mixed together and put back into the hole and soak it with water as deep as you can.

The next weekend buy your plants and plant them in this improved soil. Plant them in this hole the same depth as they were in the container. Add water to the hole as you are putting the soil back in around the roots. Make a tall ring around the plant about two feet from the trunk and six inches tall. This will be the basin or container you will use for adding water with your hose. This is important to do. Water twice a week for three weeks. Each time you water, fill the basin twice. Water once a week the same way after this.

Most of the plants you are looking for are sold locally. If you go to a nursery and ask someone for help and explain to them what you are looking for, they will direct you to “foolproof” evergreen plants for your home. There are plants that will be fairly easy to grow and then there are plants that are difficult to grow. They can help guide you. Always buy the smallest plant that is in good health you can get. Why pay the grower more money when you can grow it larger yourself?

Also, if you have been losing plants then you will not want to invest a lot until you get this growing thing down pat.

 

Some Q and As on Vegetable Grafting

Several have asked about grafted vegetables and what is the advantage. Grafting vegetables has been around for a number of years now and has had some success in greenhouse production primarily. It started in Asia and has spread to Europe, primarily where heavy cropping (high yields) and disease problems can build rapidly.

So here are some Q and A’s I grabbed from some sites to further explain it. It is not hard to do, easier than woody plants. The method I am most familiar with is using plastic tubing to hold the top and rootstock together until they grow together. Other methods are done as well.

For backyard gardeners it is mostly just for fun right now but you can buy grafted transplants for the home market.

In vegetable production in greenhouses, most of the damage from continuous cropping is caused by soil-borne diseases and nematodes. As a countermeasure to the damage caused by soil-bone diseases such as Fusarium wilt, bacterial wilt and nematodes, grafting of fruit-bearing vegetables is popular in Japan. Plants are grafted onto various rootstock species and varieties, by a range of grafting methods. Recently, the tube grafting method has been developed for plugs. This is popular in the manual grafting of tomato, eggplant and cucumber plants. Grafting robots and healing chambers have been developed, and are used in nurseries producing grafted plugs. Since grafting gives increased disease tolerance and vigor to crops, it will be useful in the low-input sustainable horticulture of the future.

Application of Grafting to Vegetable Production

The production of grafted plants first began in Japan and Korea in the late 1920s with watermelon grafted onto gourd rootstock. Eggplant was grafted onto scarlet eggplant in the 1950s. Since then, the area of fruit-bearing vegetables based on grafted plants has increased. The proportion of the area in Japan producing grafted watermelon, cucumber, melon, tomato and eggplant reached 57% of the total production area in 1980, and 59% in 1990

Objectives of Vegetable Grafting

The main objective of grafting is to avoid soil-borne diseases such as Fusarium wilt in Cucurbitaceae (Cucumber, melon etc.) and bacterial wilt in Solanaceae (tomato, pepper etc.).

Species and Varieties for Grafting

Inter-generic grafting is used in the production of many fruit-bearing vegetables, i.e. cucumber grafted on pumpkin, watermelon, on bottle gourd, melon on white gourd (also known as wax gourd). Inter-specific grafting (grafting on to a different species) is generally applied to eggplant. Scarlet eggplant and S. torvum Swartz are popular rootstock for eggplant production. A large number of varieties for rootstock have been bred and released for use by growers in Japan.

Grafting Methods for Different Types of Fruit-Bearing Vegetable

Tomato plants are mainly grafted by conventional cleft grafting. Tube grafting has recently been developed for vegetable seedlings grown by plug culture.

Cleft Grafting

The stem of the scion (at the fair-leaf stage), and the rootstock (at the four to five-leaf stage) are cut at right angles, each with 2-3 leaves remaining on the stem. The stem of the scion is cut in a wedge, and the tapered end fitted into a cleft cut in the end of the rootstock. The graft is then held firm with a plastic clip.

Tube Grafting

Tube grafting makes it possible to graft small plants grown in plug trays two or three times faster than the conventional method. The smaller the plants, the more plants can be fitted into healing chambers or acclimation rooms. For this reason, tube grafting is popular among Japanese seedling producers. The optimum growth stage for grafting varies according to the kind of plug tray used. Plants in small cells must be grafted at an earlier growth stage, and require tubes with a smaller inside diameter. First, the rootstock is cut at a slant. The scion is cut in the same way. Elastic tubes with a side-slit are placed onto the cut end of the rootstock. The cut ends of the scions are then inserted into the tube, splicing the cut surfaces of the scions and rootstock together.

Eggplant

Eggplant is grafted mainly by cleft or tube grafting. The growth rate differs according to the species of rootstock used. The number of days from sowing to grafting varies accordingly.

Cucumber

Tongue Approach Grafting

Slant-cut grafting is easy to do, and has recently become popular. This grafting method was developed for robotic grafting. It is important to remove the 1st leaf and lateral buds when a cotyledon of rootstock is cut on a slant.

Planting Watermelon

Cut grafting is popular for watermelon. A schematic diagram of cut grafting is shown.

Melon

Melon plants are mainly grafted by tongue approach grafting. Tongue approach grafting for melon is similar to that used for cucumber plants.

Healing and Acclimatization

Grafting should be carried out in a shady place sheltered from the wind, to avoid wilting of the grafted plants. Grafted plants are usually healed and acclimated in a plastic tunnel. The healing and acclimatization are very important for grafted plants to survive. The tunnel is covered with materials which provide shade and maintain inside humidity: silver/white cheese-cloth (outside) and transparent film (inside). During acclimatization, it is recommended to keep light levels at about 3 to 5 klx.

Before grafting:

• Expose the scion and rootstock to sunshine for two to three days;
• Withhold water from the plants to avoid spindly growth, and
• Make sure that the scions and rootstock have stems of a similar diameter.

After grafting, keeping the grafted plants at about 30°C and with more than 95% relative humidity for three days of healing promotes the survival ratio. Gradually, the relative humidity is then lowered and the light intensity increased. During healing and acclimatization, it is important to keep a constant air temperature in the tunnel, in order to maintain high humidity. If wilting is observed, foliar spraying of grafted plants with water is effective in helping them survive. The shading materials and films should be adjusted according to the daily weather, with more shade on a fine day.

Healing has also been mechanized. The survival ratio is consistently high when the newly developed healing chambers are used. Healing chambers in which the environment is artificially controlled are now being used by many nurseries which produce grafted plugs.

Adapted from http://www.agnet.org/library.php?func=view&style=type&id=20110803135029

Update on Tomato All Vine and No Fruit

From A Reader:
Bob, This is mostly a thank you for your answer above and hopefully providing some info for any other of your readers. If you remember my question previously....

 

Tomatoes are All Vines and Few Fruits ... Q. With five tomato plants all I really get is beautiful, huge green vine, why don't I get tomatoes? Being from East ...

I moved our little garden from the west side of the big fig tree to the east side hoping to get more sun on the tomato plants.  I can report some success with  this move.  I actually put in three plants, a Big Boy variety (still have hopes) in one of those upside-down hanging planters just outside the little garden on the west side of it.  Then a Better Boy variety on the west end of our raised planter and a Celebrity variety on the east end.  Both of these are caged and are now about 5-6 foot high.  We have been eating very nice tomatoes since the first of June.  The plants seemed to take a breather for about a week of the very hot weather but today (6 July) we took off another tomato and there are 14-16 green ones which we hope will turn.

The Big Boy did not do too well, although it may again be a sunlight problem.  It only gave us three tomatoes and they were not very big, about 1/1/2 to 2".  I actually hung the bag from a branch of the fig tree with a pole support under.  I had to constantly trim back the fig tree, and even then it only got sunlight till about 12 noon.  Fairly close and next to it is the Better Boy.  Got several tomatoes but not very big, about 2 1/2" +/-, and enough sunlight might be a problem here too.  The best performer was/is the Celebrity.  Got at least a dozen so far and they are 3-3 1/2".  I do think it gets more sunlight and this is the reason it has performed better.  I tried to treat all the same with the fertilizer and watering.

How to Water Newly Planted Fruit Trees to Maturity

Q. When I spoke to the master gardener volunteers last year about watering peaches (I had a Stark bare root from Gurney's that only made it until August) I received a wide range of answers including 35 gallons per week. Any recommended rule of thumb for watering these?

A. There are two things we have to consider when watering; how much and when. A third thing to consider is where and should be considered as the tree gets older. The how often part doesnt change as the trees get bigger. The "how much" does since "big trees use more water than little trees." The  "where" to put the water is important. As tree roots have to spread wider to anchor the tree against wind and carrying its fruit load and get enough water to support its size we have to encourage growth away from the trunk as well.

How Much. Regarding watering, give them the same amount of water as the container you would find them growing in, in the nursery. If it is equivalent to five gallon container, give them 5 gallons, 15 gallon container then 15 gallons. Even though these containers are not actually five or fifteen gallon capacity it still gives you about the right idea. Of course you can give them more than that but that would be the minimum and gauged according to size, increasing yearly until their mature size. Fully mature trees might require 30 to 40 gallons each time you water. If  possible, try to change the number, size and spacing of emitters instead of the number of minutes on the irrigation clock.

 

Example: Newly Planted 5 gal Fruit Trees (Number of Minutes Kept the Same)

 1st to 2nd Year - 4 to 6 gallons (ex. 2 each 3gph emitters, one on each side)

2nd to 3rd Year - 8 to 10 gallons (ex. 3 each 3gph emitters, triangular spacing)

3rd to 5th Year - 10 to 15 gallons (ex. 4 each 3 gph emitters, square spacing)

4t Year and Up - Replace emitters with more gph and/or more emitters

Where. Wet to an area equal to the canopy when young. As it matures the wetted pattern should be at least half the area under the canopy if possible. In commercial orchards of smaller trees like peaches and almonds under drip irrigation this "wetted area" is genearly considered in two stages.

The first stage is when they are young and a drip line is laid near the trunks with two emitters; one on each side of the trunk about 18 inches from it. The second stage as the tree approaches production, in the third and fourth years, a second drip line can be added on the opposite side of the trunk and the two lines places about 18 inches from the trunk on either side. Two more emitters are added to this new line so that the emitters are in a "square" pattern surrounding the trunk. This wets a larger area under the area under the canopy.

When. You should never have to water daily even in the hottest time of the year. The most frequent in our hot dry desert climate will most likely be every three days in peak summer water use. If you do, you run the risk of root rot or collar (lower trunk) rot. The dormant winter frequency may be 10 days to 2 weeks apart if you have mulch. Water to a depth of 18 - 24 inches each time you water.

When to Water
February 1 - April 30   Water once a week
May 1    Water twice a week (or sooner, depends on weather)
June, July, August Water three times a week if excessively hot, sandy soils and no surface mulch
September 1    Water twice a week
October 15   Water once a week
December 15 (leaf drop) Water every ten days to two weeks through the winter