Hi, Please help! I need liquid fertilizer recipes. I'm almost killed couple of my unique fruit trees with different fertilizers.
I'm in central Florida. Trying to growing tropical, and exotic fruits in my back yard. My soil is very-very poor and the trees are not growing. I like to make different homemade liquid fertilizer concentrates for Guava, Starfruit, Kumquat, Orange, Atemoya, Pomegranate, Peach,Grapes and couple of unique fruits. I'v got nutrients from a hydroponic supplier, but I can't find the right recipes to mix it, make it for soil, especially for sandy soil.
The nutrients list what i already have:
mono potassium phosphate,
and trace elements.
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Fertilizing fruits with homemade liquid fertilizer
Hi, Please help! I need liquid fertilizer recipes. I'm almost killed couple of my unique fruit trees with different fertilizers.
I do not have an answer for your specific question.
You would do your plants a bigger favor by getting some organic matter into the soil so it has some nutrient holding capacity. Mulching under the trees with an inch or two of compost (keep it a few inches from the trunk/root flare) would be an excellent start. Since you say the soil is really poor, mulch at least to the drip line -- further if the trees are small.
Like you, I always lean towards natural feeds for my plants both indoor and outside growing in the garden beds.
Fruits are greedy feeders and that stands to reason when you think about what is expected from them either by nature or by us humans so as my Grandmother would say, you will only get goodness and nutrition out of the soup pot IF you put goodness into the pot, she was right and that still applies today.
Whenever I plant any fruit, flowering trees of any type, perennials or anything that will be expected to perform well over a great number of years while growing in the same soil / large container or wherever, it stands to reason the soil needs as much added goodness as you can give / lay your hands on.
My favourite soil additive is Humus, in the form of well rotted horse manure, with horse manure you very rarely get any weed seeds or other unwanted things, Horses being grazers with adde3d Hay / straw for winter or stabled nights, there manure is the richest and best for adding nutrients, air, moisture retentive and feed to any soil where it's really impotent to have.
I work a year ahead with horse manure, It MUST be well rotted and NO smell, when you lift / hold it in your hand, it must crumble between your thumb and fingers, NOT smell like new dropped poo or ammonia smell.
Most stables or horse centre's will give this manure free of charge and as much as you want to take away. they will normally allow you to bag it up yourself or fill a trailer as they have a daily supply of the stuff. IF you go yourself, there might be fresh stuff on top of the pile, use your garden fork and remove this top layer and remove the lower stuff as this has been left to decompose for longer, 6 months old or longer is best BUT, if your digging trenches say 2 spaded deep, you can lay fresher stuff in the bottom of trench as it will rot on it's own and that deep it's doubtful any newly planted roots will go that far down until several months, so it cant burn or rot the roots.
IF you dig the LARGER than needed hole for each plant, throw a load of this manure into the bottom of hole and mix with the bottom soil, add the roots and plant making the plant sit at the same depth as was in pot or growing before, then backfill the removed soil with more added manure mixed in, at this stage, use an empty clear plastic juice container and remove bottom and cap, sink this into the planting hole at root area leaving about 2 inches above the soil, gently use feet to firm the soil around the plants and when you water, refill the container a couple of times and this will make sure the roots are getting enough water as in your heat, evaporation of water is faster than most folks imagine, wish I had a dollar for everyone who are insisting they are giving enough water yet when they are asked to test with finger down a couple of inches after watering, they then realise the soil is dry, therefore the roots are too.
The humus helps retain the moisture a little longer allowing the roots to take up the water. this container in the soil is a great way to add fertilisers and water any time required and you are sure it is going where it is meant to go and NOT running off the crust that forms on the top soil due to heat, like a pie crust.
For fruit, soil preparation is as important before planting as the care needed there after to the parts that grow above the soil.
IF you need a liquid feed for fruit, then I use a SEAWEED extract you can buy either on line or from MOST garden stores, this seaweed is natural, all the salts have been washed out and it cant harm any plants UNLESS you add too strong a mix BUT that danger applies to any weedkillers, liquid feeds or other additives, IF you make the mix too strong, it can burn the roots, if it lands on foliage, it can kill that BUT that applies with everything, if you have a prescription drug prescribed as 2 a day, if you take too many, your causing even more problems so plants are the same.
I've used the Seaweed extract for about 10 years now, I give a half dose to my indoor plants early spring at 2 week intervals, then after a couple of half dozes, I then add full strength IF required every MONTH.
other liquid feeds are from Nettles, the type that give you an itch, you cut the nettles down (NON FLOWERING PLANTS) crush them in a large bucket with your boots on, pour water over the nettles and leave COVERED for several weeks till the liquid is dark brown / green.
Dilute this strong liquid till it resembles a cup of weak tea.
Same instructions can be gained from a few clumps of cow poo, place in old pillowcase, hang in bucket make sure poo is in the water, every few days, lift and stir SMELLY water, and after about a month, dilute same strength as for nettles, (weak tea, you then water both these onto ALL plants and fruit, shrubs etc, it is an old feed long before we could buy any additive from stores, works a treat still today.
I don't know about the Orange needing the same soil medium as the Grapes as the Grapes are greedier feeders than oranges ect, so maybe go to the local library or book store to check each individual needs, some MIGHT need less feed than others or administered less frequently, however IF your fully experienced at fruit growing then just buying a book on the subject might be more helpful. I have bought paperback books while in Florida from book store, don't know IF I'm allowed to name the store but it's the one you can sit and have a coffee while you can glance / read the said book, you don't want to throw good money away on books that are expensive and of NO use and you don't know that till you get home. I spend hours in those book stores on visits as we don't have those type of outlet's here in UK.
Hope all this helps you out a bit and you can master fruit growing soon.
Lets know if it helps you out.
Best of luck and happy gardening.
I also use horse manure as a primary in my compost -- because my good friend has horses. Cow manure is even better, but none of my near friends keep cattle any more.
One of the things you need to be careful of, at least here in the US, is whether the hay fed to the horses/cattle/donkeys/lama/etc. was treated with picloram. This herbicide passes right thru their gut and into the poopy. It does NOT decompose in your compost pile. I have heard people say it never decomposes -- but as a chemist, I know that is untrue. I do know that it takes YEARS, maybe decades to be gone. If you have picloram contaminated manure, you will kill your plants.
There is an easy home test for picloram. Put a shovel full in a bucket and add water. Let sit for a day, then water an obnoxious (non-grass) weed, like dandelion. If the dandelion is healthy and florishing 3 days later, then it is good. If the dandelion is looking puny and dying, then so would your plants.
I would also encourage you to add mulch/compost/leaves, any available organic matter to the soil. That's much easier and forgiving than trying to find a mad-science concoction, and the rate at which it should be applied. Not to mention worrying about rain washing that away. You're already almost in the tropics, that's the hard part. Bringing the soil back to life and improving the tilth and fertility is not difficult, like what these plants would have in their natural habitat, just takes some time. You may be having PH issues as well. Doing things the way mother nature would takes the guesswork out, and eliminates concerns about doing more harm than good.
A healthy plant starts with healthy roots. If the soil isn't conducive to that, fertilizers can't help, they are not medicine, and too much is usually more harmful than none at all. The only thing I apply to ground plants as a fertilizer is diluted, pureťd banana water. If it's a lazy day, maybe burying the whole peel at the base of a plant expected to bloom soon.
Compost tea might be a helpful addition to your regime, and from your expression of enjoying the making of the fertilizer concoctions, it seems like it would be enjoyable for you to do this for your plants.
Hi, Thanks for the quick respond Bluetexasbonnie, WeNel, Purpleinopp.
I have to think about again, what I need to do. I'm already tried cow manure, and different things. I wasn't really happy with the result, maybe I did something wrong. The "normal" care of plants look a like not working in my area. First the problem with the watering. My calcareous, sandy, loose soil drains very quickly and are not able to hold nutrients because water carries these nutrients away very quickly. Somebody told me that he saved his trees with liquid fertilizer. The nutrients I ordered for hydroponic, but never started, because, the air is very humid, hot. So I was thinking Iím going to use it, to make liquid fertilizer. I love gardening, but here in central Florida is a so different then other places, that sometimes Iím stock. For example, the many squirrels in our area. They eat the unripe tomatoes, all my fruits and Iím already tried so many things, and nothing seems to work. I live in area, where the simple gardening routines are not working.
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Organic matter helps sandy soil retain moisture, and helps clay soils to loosen and drain. In both it gives a place for plant nutrients to be absorbed and retained for a little bit. It isn't an instant cure. Good soil takes years to build. Keep adding the compost and things will get better every year.
Organic based fertilizers are not as mobile as chemical based fertilizers, and so hang around longer. The nutrients are in a cationic form (have a positive charge). In the traditional salt/chemical fertilizers, the nutrients are in an anionic form (have a negative charge). A plant can absorb in either form.
Part of making good soil is getting a nice large population of micro-organisms going. The anionic form of plant nutrition (i.e. so called chemical fertilizers) is disruptive to some of the most beneficial micro-organisms.
Well said, Bonnie!
Cspista, think of gardening as growing from the roots up, not from the foliage down. The soil here is very sandy also, and giant trees are very greedy about using all of the moisture. Fertilizer won't help keep plants from drying out, like you said. If you're having to water a lot, and using tap water to do it, that's even more problematic since there are likely chemicals like chorine/chloramine/chloride, fluoride, lime that can alter the PH of soil and generally harmful to plants. If there is more organic matter in the soil, and especially a layer of it on top, the moisture can't evaporate as quickly, and less supplemental water is needed. Composted organic matter also contains all of the nutrients plants need in a form they can use. Nobody fertilizes out in the wild.
Purplein opp is right, your getting so stresses out about fertilisers not working, plants are like babies, they need nourishment, water, heat, warmth and some tlc, but IF there is no firm foundation (GOOD SOIL STRUCTURE) then the other things ?needs I mentioned are NOT going to help as there is nothing in the sandy soil to help hold the goodness in place.
I told you at start you need to give the planting area a good going over with humus to enrich the soil as it helps retain moisture, air, nutrients, cool roots and holds onto moisture longer than sand, sand has NO goodness in it and adding Liquid feeds with out improving the soil structure, is like building a house and laying the bricks on top of each other WITHOUT adding cement for structural strength.
I cant think your fruits will be around too long without starting to improve their foundations and growing medium.
Hope all this very helpful and tested advice you have been offered from all the folks above will help you understand that liquid manure is no real substitute for good humus rich soil regardless how you get it, leaf mould is great for fruit as a top mulch but I would not use it as a soil conditioner as it wont have the same nutrients as manure, home made compost or similar, IT'S a no brainer really, fruit is a greedy plant and when you think of what it does in nature, you can understand why it requires fertile soil.
Best of luck. WeeNel.
I like that too, WeeN! Nicely said.
This woman speaks well of these things...
Take a water sample to a pet store where they will test it just you were starting an aquarium.
Get the actual test results, the numbers!
Here is what to test for:
You could also look at a water report from your municipal water supply.
Then post back with those results. I will fine tune my suggestions when I see what is in your water.
The other people are right: Add LOTS of organic matter to the sandy soil, both mixing with new planting and as a mulch. Gotta go to work, more when I get back.
calcium nitrate, SKIP IT. WATER already has too much Ca
potassium sulphate, GOOD. USE PLENTY.
potassium nitrate, GOOD. USE MODERATE AMOUNT.
mono potassium phosphate, GOOD. USE SPARINGLY TO MODERATELY.
magnesium sulphate, SKIP IT.. Water probably has enough Mg.
amonium nitrate. GOOD. USE MODERATE AMOUNT.
Epsom salt. SKIP IT. WATER probably has enough Mg.
and trace elements. GOOD. USE SPARINGLY.
Thanks Diana! I'm going to make a water testing. Everybody has right, but I'm still very confused, cause everybody is thinking on normal soil condition. My soil is not normal! I live close to the coast (150-200 yard), the groundwater seems to be OK down to prox. 8 feet, but if I try to get water from deeper, more and more salty, finale the water is like the seawater. So I've got a 1300 gallon rainwater tank for watering. I like organic gardening too but now I like to try something else. Iím from Europe, and this loose, sandy, calcareous salty soil is just not working to me. Nothing seems to work here what I learned before. Anybody have soil condition like that? In the neighborhood somebody said, the main problem that the soil turns with the time acidic, and I need to add garden lime to the plant. What? Are you joking??? The Florida soil is nothing else, just almost pure calcium! I'm not so beginner like I'm looking, just I do not know what to do in this unique condition. I was a good boy (61 Years old), before I planted the trees, mixed the soil with organic compost. Every spring I have feed with cow manure, or with the right the fertilizer, I have covered with mulch. Is just don't work! I need to learn something special, to keep it growing my trees in this conditions. For example: I have to stop making compost. We can't joy the backyard anymore, because I'm actually not making compost, I just making new perfect home for the incredible amount of different bugs, and fly, mosquitoes around my house. Here is no frost to kill the bugs, they just multiplying like a crazy in the compost. Everything is different here.
Like I said I have nutrients for hydroponic, and never used. I like to use it somehow to tune up my trees. I had to put the trees in the ground in the hole surround it with plastic, because in the dry season the dry sand take away every drop of water when I trying to watering my trees. Nothing is ďnormalĒ here with the soil. Some other people plant the trees in Florida in the ground with the plastic container to keep the moister around the roots. In normal condition this is ridiculous. But here is not! My 3 years old peach tree branches (planted directly in the soil, and fertilized every year with 2 inches organic cow manure in the spring) grow this year prox. 3-4 inches!!! In normal condition the new branches should be at least 3 feet long!! Now my tree is smaller then was, when I bought.! Other fruit trees growing in my backyard very well in containers (most of them in ugly looking big plastic garbage cans). Maybe I'm going to cut off the bottom of the can, and dig a deep hole, and put the tree with the garbage can in the ground. I have already seen something like that. That's crazy here. For example in the summer you can't grow tomato, and vegetables, because heat, and moisture, But in autumn, and Winter Yes! So, now is the time here in Florida to make tomato seedlings. When my house was build, then the builders took away the top layer of the sol with big bulldozers , and moved around in the neighborhood to make it flat, and finally now I donít have a really soil, just calcareous pure sand in my backyard. Some of my neighbors have a useful soil, I'm not.
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cspista, I am so sorry but you really are missing the whole point of the Information given by everyone about IMPROVING your SANDY soil,
I live right on the sea / ocean, waterway or whatever you want to call it, My natural soil here on the West Coast of Scotland is real sandy soil, to grow anything, sand is absolutely no use, it has grains of sand that CANT hold onto water as there is no real structure to it, in lot's of garden where the soil is heavy, stays wet and cold, they ADD sand to that soil along with some small gravel, (gravel is like larger grains of sand) this being added to help drain the soil as heavy soil stays wet too long and most plants other that Aquatic's cant take the cold wet heavy soil as it has no nutrients, these are run out from the soil when more rain soaks the heavy soil, there is no air in the soil and nutrients cant be taken up by the roots, SAND mixed into this heavy soil helps.
You soil is the very opposite, it is so free draining that you can pour gallons of Hydroponic feeds, even more gallons of water, any amount of plant fertilisers and guess what, your sandy soil with still be sandy and still be unable to take in the nutrients your trying to offer the plants.
I don't know what you didn't like about the cow manure unless it was FRESH laid manure, no one likes that stuff, you have to take old, well decayed manure from any type of animal, the fresh stuff is full of Ammonia and that can burn the roots or leaves of plants, the nutrients on fresh manure cant be transferred to the roots where nutrients are most needed because the manure has not rotted down causing the break up of the structure of poo which releases the nutrient because the rotting process causes nutrients to be released as the poo decomposes.
Never use new fresh smelly manures, the heat generated when rotting down kills off any bacteria's, bugs, seeds from grass and weeds the animals have eaten and passed through there gut and body, so rotted manure is safe to use and the best you can add to ANY soil BUT best for sandy soil.
You continued problems will not go away while trying to grow fruit, these are greedy feeders,
they need a load of nutrients to make flowers and the flowers form the fruit, the fruit in turn need water to swell the fruit, all fruit needs huge amounts of water while fruit is forming.
Think Grape, what is inside a Grape, juice and juice can only be made IF sufficient water is available at the roots to turn the water into a sugary juice as the fruit expands.
Hydroponics are a different class/ type of growing plants, these are grown in very special sterile conditions where the roots are growing in a special container and only liquid with the added Hydroponic feeds added at intervals regulated by timers, temp's and light, NO soil, sandy or otherwise are used so I think you are getting your info mixed up and trying to combine them is NOT working.
I would for my last suggestion take yourself off to a library / book store and have a read through books on Hydroponics, AND growing conditions for fruit, soil improvement will also be there for the reading and I feel sure IF you borrow a library book on fruit growing AND hydroponic growing, you will understand why ALL the above gardeners are telling you to add as much humus / manures or compost to your soil to help the NEW SAND, MANURE MIXED SOIL, give the plants the care and treatment they need before they drop dead trying to grow in the impossible conditions you are offering the plants at present.
Hope this clears up your obsession with using just sandy soil without trying to improve the soil STRUCTURE. I've added all the stuff I recommend to my sandy soil and I grow fruit, Veg, various trees, Rhododendrons and others of that type of soil (acidic) I have several Perennial borders and beds so Please believe me when I and others are telling you to forget liquid feeds until you improve your soil enough to let the improved soil help store the feeds you want to pour into sand, Have you even been to the beach and poured sea water into a hole in the sand, it just runs through the sand, that's what is happening to the soil your trying to grow fruit tree's / shrubs in and it cant hols onto water, feed or anything.
I don't wish to appear rude but am trying to encourage you to rethink how your growing the fruit AND obviously still having many problems doing so, I and everyone else is hoping you will have success but we cant make you change your growing methods or your unsuitable soil conditions as it is at the moment, but we can all hope you at least try out the methods were offering as the best advice for you, our help and advice is gained through experience not hot air.
Good luck and Best Regards.
Good soil is a blend of mineral particles and organic matter. The mineral particle sizes are called sand, silt and clay. The organic matter is decomposing plant matter (mostly). Depending on the plant, a blend of up to 50% organic matter with the right ratios of mineral particles can make a really good planting mix. A soil type that is so one sided (almost all sand, no organic matter) is very poor for almost all plants.
Soil that is pretty much pure sand has no ability to hold nutrients.
Humus is broken down organic matter, that is small enough to hold nutrients. Humus has high Cationic Exchange Capacity.
Clay soil has high CEC, too, and it does not take much clay in a soil to do this.
Constant source of salt (sodium chloride) from the ocean spray and ground water is VERY hard on plants. The ocean water is also very alkaline. It is also very high in the minerals that plants need to live, but the high sodium chloride and high pH are so toxic that the plants cannot benefit from the other minerals in the water.
Best thing you can do is to keep on washing it away with as much rain water as you can collect.
To fertilize the plants with the chemicals used in hydroponics, agriculture and aquarium plants is pretty easy.
The problem is that they chemically act similar to sodium chloride, like a salt, and can burn the leaves and roots if they are applied too often or too strong. They will not stay in the sandy soil, and will get washed out when you deep soak to dilute the ocean water.
I would use the chemical fertilizers as a foliar feed. VERY reduced dosing.
As for fighting the sandy soil and ocean coming in from the water table:
I would build raised boxes and fill with a blend of soil that has finer particles than the sand and lots of organic matter. Perhaps:
the mineral fraction would be
not higher than 30% clay.
the organic matter part would have no manures. Composted wood shavings is better. Home made compost is good. Broken down leaves are good if they come from plants grown inland, away from the ocean breeze on salt-free soil. composted lawn clippings are good.
Do not use manure from bags. It is collected in feed lots and can be very salty. Even pasture raised horses and cattle can have salty manure if they are on salty pasture or are fed a lot of bagged feeds in addition to the pasture grass. Chicken and rabbit manures can also be high in salts. These are also collected from caged animals that are fed dry foods that can be high in salts. When you already have salt coming in from the ocean I would avoid it in any other form.
I still see the need for drainage in raised beds, so I would not put a solid bottom in it. If you have gophers or other digging pests then a fine mesh would be good. If you feel you want something in there, then look into filter fabric or weed mat. This would slow the water flow, but not stop it so the beds would have drainage. You could make individual boxes for each tree, or make a larger box and plant a couple of dwarf trees. Add vegetables to the boxes, too.
1' deep for pretty much all vegetables, annual and perennial flowers, smaller shrubs. Almost any container can work for this. Just make sure there is enough drainage and buy potting mix in bags if you are just doing a few. The garbage can, storage bin, 5 gallon bucket idea is this exact idea. Around here used wine barrels are often used for planters. Many people build such boxes for their vegetables. Almost anything will work for the sides, a foot of soil is pretty easy to support. If you build boxes that are 4' wide x 8' long and 1' deep, these are common lumber sizes, then line it with filter fabric and fill it with good soil I think this would be really great. Each box 4' x 8' x 12" deep would need over a cubic yard of soil to fill it. Just use 1 cubic yard and allow the space so you can top it off with mulch. 4' wide is a good width, too. Many people can reach about 2' so you could plant, weed and harvest without having to stand in the boxes. This compacts the soil, not a good thing.
2' deep for dwarf trees and most mid sized shrubs. It takes a stronger container, more like a dedicated box, retaining wall or similar. If you are making more than one of these perhaps 3-4' square by 2' deep you will not want to buy bagged soil. Get it by the truckload.
3' deep for semi-dwarf and full sized fruit trees. Again, buying bagged soil is way too expensive. Get a truckload of it delivered. One box, 3' x 3' x 3' is one cubic yard.
Another way to do this, not build boxes, is to make raised planter areas with rock retaining walls.
Let me know if you want to look into this, and perhaps I can work out a design for you. (I do this sort of thing all the time)
A variation on the retaining wall, easy to do, but only safe for the shortest beds:
Make any shape you want (square, rectangle) out of concrete blocks. These are construction shapes that are 8" x 8" x 16". You could stack up 2 of these with nothing to mortar them and they would stay standing up when you filled the shape with soil. Alternate the blocks when you lay the second course over the first. This would give you a bed 16" deep.
Next, check the plants that are not doing well.
There is a root pest that is very common in sandy soil called root knot nematode. No matter how good you are treating the plants, if they are infested they will not do well. Dig up a plant that is on its last legs anyway, and look at the roots. Are they normal? Most plants have fine hairy roots when they are small, and the hairy roots grow out into smooth branching roots. Look up some pictures of roots infested with root rot nematode to see what you are looking for.
Hi everybody! Thank you very much for the useful and detailed info. They are very impressive.Thanks for spend so many time to help me out! I learned a lot of important things again. I planted couple of small trees already in whiskey barrel, some of them doing very well.
I guess Diana just figure it out my really problem. I know that our soil has a root knot nematodes infection. I see the knots every time, when I pull some sick tomato seedlings out. But I didn't realized, that this infection can affect so badly my trees too. I tried to get under the control before with organic staff made for nematodes control, with no effect. Somebody told me, that is no really solution to control this microscopic worms.So I stopped to control it. I have find online before some living beneficial nematodes to fight to the bad nematodes, but never tried. Look alike home depot has it too. I have to try again. University of Arkansas agriculture division wrote: Several products claiming to control nematodes are available. Most of these products are either biological control agents or organic compounds that are added to the soil. There is very little research data to indicate the effectiveness of these products in home gardens.
Wikipedia wrote: Root-knot nematodes (Meloidogyne spp.) can be controlled with a biocontrol agent Paecilomyces lilacinus, Pasteuria pentrans. Jugloneeffects on Development of the plant parasitic nematode (Meloidogyne Spp.) on Arachis hypogaea L. Napthoquinones controlling the root- knot nematode Meloidogyne spp.
The available products are "beneficial nematodes". I can not find a product has a detailed info, what kind of living things are in the box.
So what are you guys think about this?
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I know biologicals work.
Usually they take time. The pest problem took a while to build up, and the predator will need time to build up. The populations might see-saw a few seasons before they stabilize. Keep applying more and more beneficial organisms to keep the balance in your favor. As the beneficials get ahead of the pests then there is less food for the beneficials.
Remove, throw away any badly infected plants. They are harboring a reserve, breeding population of the pest, and will not recover.
Work on control for a year or two, incorporating as much soil conditioner (organic matter) into your soil as possible. Then solarize. This will kill a lot of pests in the soil. Then add the nematode parasites. If you can find out which species of nematodes you have, then target those. Perhaps get a couple of different parasites. Maybe one will do better than the other. After you have solarized the parasites will be deeper in the soil, so water in really well when you add the predators.
Plant in raised beds. Fill these beds with the best possible blend of soil and compost according to the plants you want to raise. The nematodes in the soil directly under the raised planters will eventually work their way up. Minimize this in several ways.
1) Solarize the area before you start. I did this many years ago in a pattern in a field (large rectangles for vegetables) and used some of the solarized plots and did not use a few others. A couple of years later the weeds were still growing differently in the plots that we had solarized but never did anything more.
2) Add the predators.
3) Put some filter fabric down if you want to help hold just a bit of water in the raised planter.
4) Keep adding organic matter and predators each year. Keep the soil in the raised planters better for the plants and less attractive to the nematodes.
If you want to use your (infested) soil, then solarize it to kill the nematodes. This is best done during the hottest, sunniest weather.
If you do not want to use your soil, then check out the bulk material you buy, before you buy it. It is probably local soil, and just as infested, so not worth the money.
How to solarize bare soil:
Soak it well (hard to do in sand!).
Add soil conditioner, compost... rototill.
Water it again.
Spread clear plastic over the area. Weight down the edges so there will be no wind lifting the plastic. You might lay down some lumber, or shovel soil over the edges.
Let it sit for several days (in the hottest, sunniest weather) or a week or two (mild but still sunny) or longer. Cloudy days do not count.
How to solarize much smaller amounts of soil, like several cubic feet- enough for a very small planter.
Build a box of whatever size you like, but see the rest of the instructions for some ideas.
The lid will be glass. If you have an old sliding glass door, then the box can be quite large. Acrylic will work, but it needs to be thick. It will sag if it is too thin.
The rest of the box should be about a foot deep. For example, if you build it out of 2 x 12, that is good.
If you can tip the box to aim it at the sun this is a bonus, but the box needs to be stronger.
If you use thinner lumber or other material, then insulate the box. Caulk the gaps. You do not want air exchange. Cools the interior too much.
Spread the well moistened soil in the box. If it is only an inch or so, then one treatment is fine.
If it is 2-3" then treat for a while, then stir it and treat again.
Use the timing suggested above: a few days to a week for nice weather, more than a week if it is cooler.
An interesting thing to do is to put an (old) oven thermometer in the box, or under the plastic sheeting. See how hot it really is getting under there!
If you have a soil thermometer or compost thermometer or even a meat thermometer stick it in the ground under the plastic and see how hot it is getting a few inches under the soil, and even deeper.