That sounds ambitious. But with zero garden experience and in a new site you might be better off with a much smaller bed, with the idea that you could expand it later, and gain some experience. For example, in a raised bed, it's still good to have some idea abut what's underneath, and the permeability of that soil. You get that info by digging the soil, and gardening there for a while, ideally with a raised bed on top of it. It would be unfortunate if you put in a large bed (you didn't mean 90 square feet with 25-40 foot sides, did you?) and after it was all done, decided later on some preparation you should have done on the base layer but didn't.

I agree with daninthedirt. Plus for many reasons the base of a tree isn't an auspicious place for a vegetable garden, either from the vegetables' or the tree's point of view. Do you have an area out in the open you could use? I would also suggest experimenting with the native soil before dismissing it. Who knows, with some amendment it could be fine for gardening and cost a lot less than building a raised bed from scratch. Some crops prefer a loose sandy soil - carrots for example. 300 dollars is a huge outlay imo and I'm pretty sure you could spend far less and have a nice starter garden to build up from.

25foot sides means over 600 square feet....which would require well over 20tonnes of topsoil (at around 1foot deep)

That is a very ambitious project, but your best bet would be ask in the FL gardening forum, where people understand about things like sugar sand and nemotodes and the wide variety of micro climates down here. Many people use a combination of raised beds and containers.

But I agree that one wants to know more about that tree and the overall situation of the location where you're planning to do this.

It can be done, though. You might want to read this thread and watch the video (long) made by another FL beginner who really went all in. It gives a good idea of the work involved.

Here is a link that might be useful: veganbob's garden

Yes, I was going to mention the tree making it an inauspicious place, but for a bed with 25-40 foot sides, the tree would affect only a small piece of it.

Incidentally, LarryLido, if you're anywhere near Orlando, you might want to try to get to Silvia's garden party tomorrow. Nobody, but nobody makes better use of a not-so-large space than she does and you'd meet a lot of experienced gardeners from your part of the state:

Here is a link that might be useful: Silvia's garden party thread

Lol....those dimensions are scary for a first time gardener!

But I am most concerned about the health and well being of the tree. They do not welcome having their roots disturbed, whether by compaction, burial, digging, or anything.

If the tree adds any value at all to the property, then the root/soil system needs to be protected.

But you need to find a materials calculator to help you figure out accurately how many cubic yards of good top soil and amendments you would require to fill a raised bed 18 inches.

I'm guessing that it would bust your budget just to build the frame. Add to that the cost of many cubic yards of fill materials, seeds, plants, fertilizers, hoses, pest management products, tools, etc.

Perhaps you can find room for a much smaller garden away from the tree, its interfering roots and shade.

Are you planning on canning, freezing, selling your veggies?

Have to agree with the others. Keep the garden away from the tree. And either I (and everyone else) am misunderstanding what you mean or your math is way off when it comes to the size of the garden.

"Im thinking the garden would be rectangular and around 25-40 feet per side. So something like 90 square feet."

A 25x25 foot garden would equal 650 square feet. A 9x10 foot garden, which is a much more manageable size for a beginner, would be 90 square feet.

Rodney

Tree roots are just part of the problem when raising veggies, most veggies require at least 8 hours of direct sun light to produce well so consider the shading effect of the tree.

Sorry, but most veggies do not require 8 hours of direct sun to produce well, especially in the south, where the heat can be fierce, and shadecloth is commonly used

One would need 2 to 3 hours per day of work through out the season to manage the garden in such a large plot. And as all of us know that it is really hard work.
Design the plot so that trees remain in East and North side of your garden.This way plants will have enough sun light.

I'm quite familiar with FL sand.

Also, "base of tree" , if it is in fact quite tree-sized, then do yourself a big favor and don't waste your time. Gardening is a long-term investment of effort and money. I wouldn't waste it on someone else's property unless conditions were near ideal.

Another thing that I don't get much of a sense of from your first post is that raised beds are generally made quite narrow, because you don't want to have to walk in them, so they are usually designed so that you can easily reach all parts of the bed from outside it, so three or four feet wide or thereabouts, so like everyone else I'm still having a hard time envisioning what you plan to do.

8 hours of direct sunlight up here in Va does my wide selection of veggies just fine for maximum production, and for a certain number of my favorite varieties 10 hours would do even better for both quality and produce. My melons would not be as sweet nor my corn ears big and fruitful with less than 8 hours. I suppose it's what the OP is planning to grow? But under a shade tree is not ideal in many ways.

I'm with Conchita! 3-4' wide at the most! I started with an 8x8 ' bed, then found this forum! I was able to change it to 2 3x8' beds with a path down the middle.
All other beds have been 4x8' and a couple of 3x6'.
Be sure you allow enough path space to maneuver a wheelbarrow and be able to turn and dump it. That was another mistake I made was not enough room in the paths to do wheel barrow work! (You or the later tenants will always have to add compost or more soil each year)
Also, since you will be leaving these wonderful beds for the landlord, can't he pitch in and you do all the work? He's going to get the gardens in the long run!
Even my skinflint neighbor landlord paid for the materials for his tenants to do some beautiful landscaping! He was able to up the rent by a couple hundred per month cause of the work the tenants had done over several years! Now their daughter has moved in and let everything die! Nancy

I just read Larry's post to my husband and he thinks that Larry is joking with us! I confess, the thought crossed my mind, lol.

I suggest you spend a few dollars and get a soil test from your local Agricultural center. Then you will know what you need to do to improve your soil. It only costs $7 here. You get a free consult with the horticulturist. The lab results are hard for most folks to understand.

Save the time and money - all that one needs to add to florida sugar sand is everything a crop needs. There is adequate Ca and P in florida sand, but it requires a lot of OM and time to get enough microbial action to make it plant-available.

The best thing one can do is dump a foot or to of leaves and landscape chippings/trimmings on a plot and leave it for a year or two, as a good start.

Surprised I did not see this posted yetâ¦.

Here is a link that might be useful: Florida Veg Gardening Guide from U of FL

I kinda agree with your thinking pnbrown. But it seems like playing a guessing game, not knowing for sure what is in the soil. IMO, It depends on what the land was used for before.

I think rhizo's right (or her husband, anyway), given that the OP has never been back yet.

Although you may have 25-40 feet of available space in one direction, I would also suggest that you can split those up into smaller and more manageable plots. Take the typical size of 4x4, and you can start with 1-2 of them. As the time and years go by, you can expand to cover more of the 25-40 feet if you want.

You'll get your feet wet that first year, and that will either let you know how much you find that you enjoy gardening, or how much you dislike it. Either way, 1 or 2 4x4 will be more manageable and you won't feel disheartened compared to if you had invested too much time or materials.

Zackey, that's true, commercial citrus was all over central FL. We tested the new garden site at a lakeside place a few years ago and it was oddly high in copper (though not toxically high) until one remembers copper sulfate's use as a fungicide. It was very high as compared to normal for central fl sand (almost zero).

Our property was a cow pasture before we moved here. My hubby doesn't want to soil test and I do. An on going battle.They mixed all kinds of soil in and took down trees. Built up our lot with soil removed to make the neighbors pond. God only know what we have.