Growing media for raised bed blueberries?

I grow fruit, including blueberries, in pots, but NOT raised beds. A neighbor has asked me to help her with her blueberry plants. Her blueberry plants are in ground and don’t grow. Our soil isn’t blueberry friendly. So I’m thinking raised beds may be a good choice for her.

So I have questions about blueberries and raised beds:

  1. How tall should the raised beds be? (Taller means more money and effort to build. But taller means a deeper growing column.)
  2. What is a good mix to grow in?
  3. What is required to keep the mix acidic?


My Southern Highbush are grown in beds 3 feet wide and about 4-6 inches high in a mixture of ground pine bark, peat moss and soil. The pine bark and the peat moss will lower the PH and I added some granulated sulfur also. You did not specify the type of blueberry, but Rabbiteye blueberry are easier to grow in their native climate than other types because they are not as demanding about organic matter, low PH and the proper amount of water

I grow blueberries in raised beds. I use pine bark fines, peat moss, compost in peat moss, and a small amount of garden soil. I use sulfur to keep it acidic. I also use sulfuric acid in water for quickly adjusting PH. I use rainwater to water with. My beds are 12 inches high.
Here is Chandler, hard to see over 4 feet tall.

I grow in-ground here in NYC, I replace 1/3 of the soil with pine bark and peat moss, additionally 1 cup of sulfur to planting hole and then again every 6-12 months or so.

I use DWN’s instructions, and they have worked very well for me:

I find that growing them in pots is good, but it is easier to do it in raised beds.
Less water, more root room etc. Unless you’re in CA or the like, you can’t leave the pots outside unprotected. This is a huge hassle for me.

Thanks all, for your information and ideas.

Can you elaborate on DWN’s “forest-byproduct-based potting soil (azalea mix or acid plant mix)”? Local stores sell potting mix for acid loving plants, but it’s mostly peat. Thanks.

You commented, " I use pine bark fines, peat moss, compost in peat moss, and a small amount of garden soil." Can you give me an idea on proportions / percentages? Thanks.

You can use equal amounts of pine bark and peat. I myself prefer 3 parts pine bark, 1 part peat, 1 part compost in peat moss (skip if you can’t find). 1 part garden soil. and 1 cup of sulfer, or use Espoma soil acidifier. Add 1 cup once or twice a year.
Finding the right size pine bark is tough. You want small pieces, and not powder. Some soil conditioners are perfect. Look for soil conditioner. Composted pine bark is better, although it doesn’t last as long.
I would mound the middle up at least a foot, plant in mound.

Only somewhat related but how do you grow the ones you have in the pots currently?

In general, most of the blueberry roots are in the top 6" of soil, slightly more if the soil is good. So be prepared to provide at least 10" of good soil. No matter how you mix the soil, the soil mix has to be light weight, good water keeping and excellent drainage.


Fruitnut is the expert here on growing fruit in pots. So if there’s ever any conflict between what I write and he writes, follow fruitnut’s advice.

POT: 14 gallon rubbermaid tote with drain holes drilled in the bottom. (fruitnut grows in smaller pots.)
POTTING MIX: This mix is for acid loving plants like blueberries: 1/2 sphagnum peat moss, 1/2 pine bark fines (tiny chips of pine bark mulch. The big stuff is NOT ok.) If you want to lighten the pot, you can use maybe 10% perlite. 1 cup of gypsum for 14 gallons of potting mix. I mix in a slow release fertilizer for ACID LOVING plants, but it’s only good for the first few months.
WATER: Must water EVERY day unless they are dormant (winter). And even then, don’t let them dry out.
FERTILIZER: Because this isn’t “dirt”, you must provide all the food your blueberry needs. Fertilizer for ACID LOVING plants ONLY. Standard fertilizer can kill your blueberries. If your fertilizer does not provide magnesium, occasionally apply some epsom salts. If your water doesn’t contain calcium, apply more gypsum once a year.
WINTER: I live in zone 5. I grow several northern high bush varieties. If they were planted in the ground, they’d survive the winter just fine. But in pots, if left unprotected, they would die. The pot sits above the ground so the roots are exposed. If you live in a cold climate (Bahama? Dan), you can either drag them into an UNheated indoor space. Or, you can bury the pot in leaves.
BIRDS: The birds would take every last berry if they could. I built a simple pvc frame and throw a bird net over that. (if you just throw the bird net directly over the bushes, it will snag and rip the berries off.)

These ingredients, except epsom salts, should be available at any store that sells garden supplies. Epsom salts are sold in the pharmacy area of Walmart, etc.

As Drew pointed out, growing in raise beds has 2 advantages. 1) You won’t have to water as much, 2) You don’t have to protect your plants from winter.

If you have more questions, please ask.


I am kind of new to growing blueberries. I killed several trying to grow them in the native soil mixed with peat moss and watering them with alkaline water. Last year instead of making the raised bed, I dag a ditch about 3-4 feet wide, 10 feet long and 3 feet deep (maybe too deep). I covered walls with plastic sheets to prevent native soil coming into the ditch. I put some wooden logs on the bottom, which I needed to get rid of. I mixed 1 bag of peat moss with 1 bag of pine bark and about the same volume of shredded oak leaves, which I have I abundance. It took about 7 or 10 volumes of that mix to fill the ditch. I planted 6 different varieties of blueberries in it. They grew very well the last year. In the winter I added loads of oak leaves on the top of the bushes, they were literally covered with them, blueberries need a lot of organic matter. This year I added sulfur and holy tone fertilizer two times, and the bushes grew like crazy, I want to increase their green mass, so I’ll have more berries next year. This year I had just a few, since the bushes were kinda small.
I choose to make a ditch instead of raised bed, to reduce watering, since our city water is very alkaline and the acidifying water takes an effort. The oak leaves made very good mulch, no weeds are growing around the bushes and again it helps to save water. So far my method works. I hope to have many blueberries next year.

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Sorry, I forgot.
MAINTAINING ACIDITY: 1) If your water is alkaline, consider adding regular kitchen vinegar to acidify the water. I probably should do that EVERY time. But I only do that occasionally. 2) Every fall I add a handful of garden sulfer to the soil.

Sounds like your approach should work. I’ve read that people who simply dig out their soil and replace or amend doesn’t work over time because the acidity equalizes with the surrounding soil. Putting up a barrier to the neighboring soil is likely to solve that problem. For a different purpose and a different fruit, I used a similar approach but I used a roll of roof flashing. to coral off the walls. For other readers, I’d like to point out that the bottom should NOT be a water proof barrier.

I have to add as much as 2 tablespoons of distilled white vinegar per gallon for my alkaline well water.

I made several pictures of my bushes, those that grow in the ditch.

This is sunshine blueberry on the second picture. It surprisingly survived our winter and had a few sweet berries.

This is pink lemonade, big bush, but had not a single flower this spring.

And this is supposed to be chandler with a lot of new growth. It almost died when was planted in the native soil.

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Pink Lemonade is finicky here too, took a good 3 growing seasons to get it to set flowers and fruit. Not sure so much about the flavor, the novelty is nice, when mixed with other red berries they don’t turn everything purple, so it’s got that going for it. I’;m going to give it another year or so.