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pH Preferences

Trees, Shrubs, Vegetables, and Flowers

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An accurate soil test will indicate your soil's pH level will specify the amount of lime or sulfur that is needed to bring it up or down to the appropriate level. A pH of 6.5 is just about right for most home gardens, since most plants thrive in the 6.0 to 7.0 (slightly acidic to neutral) range. Some plants (blueberries, azaleas) prefer more strongly acidic soil, while a few (ferns, asparagus) do best in soil that is neutral to slightly alkaline. Acidic (sour) soil is counteracted by applying finely ground limestone, and alkaline (sweet) soil is treated with gypsum (calcium sulfate) or ground sulfur.

Common Name Optimum pH Range
Trees and Shrubs
Apple 5.0-6.5
Ash 6.0-7.5
Azalea 4.5-6.0
Basswood 6.0-7.5
Beautybush 6.0-7.5
Birch 5.0-6.5
Blackberry 5.0-6.0
Blueberry 4.0-6.0
Boxwood 6.0-7.5
Cherry, sour 6.0-7.0
Chestnut 5.0-6.5
Crab apple 6.0-7.5
Dogwood 5.0-7.0
Elder, box 6.0-8.0
Fir, balsam 5.0-6.0
Fir, Douglas 6.0-7.0
Hemlock 5.0-6.0
Hydrangea, blue-flowered 4.0-5.0
Hydrangea, pink-flowered 6.0-7.0
Juniper 5.0-6.0
Laurel, mountain 4.5-6.0
Lemon 6.0-7.5
Lilac 6.0-7.5
Maple, sugar 6.0-7.5
Oak, white 5.0-6.5
Orange 6.0-7.5
Peach 6.0-7.0
Pear 6.0-7.5
Pecan 6.4-8.0
Pine, red 5.0-6.0
Pine, white 4.5-6.0
Plum 6.0-8.0
Raspberry, red 5.5-7.0
Rhododendron 4.5-6.0
Spruce 5.0-6.0
Walnut, black 6.0-8.0
Willow 6.0-8.0
Asparagus 6.0-8.0
Bean, pole 6.0-7.5
Beet 6.0-7.5
Broccoli 6.0-7.0
Brussels sprout 6.0-7.5
Cabbage 6.0-7.0
Carrot 5.5-7.0
Cauliflower 5.5-7.5
Celery 5.8-7.0
Chive 6.0-7.0
Cucumber 5.5-7.0
Garlic 5.5-8.0
Kale 6.0-7.5
Lettuce 6.0-7.0
Pea, sweet 6.0-7.5
Pepper, sweet 5.5-7.0
Potato 4.8-6.5
Pumpkin 5.5-7.5
Radish 6.0-7.0
Spinach 6.0-7.5
Squash, crookneck 6.0-7.5
Squash, Hubbard 5.5-7.0
Tomato 5.5-7.5
Alyssum 6.0-7.5
Aster, New England 6.0-8.0
Baby's breath 6.0-7.0
Bachelor's button 6.0-7.5
Bee balm 6.0-7.5
Begonia 5.5-7.0
Black-eyed Susan 5.5-7.0
Bleeding heart 6.0-7.5
Canna 6.0-8.0
Carnation 6.0-7.0
Chrysanthemum 6.0-7.5
Clematis 5.5-7.0
Coleus 6.0-7.0
Coneflower, purple 5.0-7.5
Cosmos 5.0-8.0
Crocus 6.0-8.0
Daffodil 6.0-6.5
Dahlia 6.0-7.5
Daisy, Shasta 6.0-8.0
Daylily 6.0-8.0
Delphinium 6.0-7.5
Foxglove 6.0-7.5
Geranium 6.0-8.0
Gladiolus 5.0-7.0
Hibiscus 6.0-8.0
Hollyhock 6.0-8.0
Hyacinth 6.5-7.5
Iris, blue flag 5.0-7.5
Lily-of-the-valley 4.5-6.0
Lupine 5.0-6.5
Marigold 5.5-7.5
Morning glory 6.0-7.5
Narcissus, trumpet 5.5-6.5
Nasturtium 5.5-7.5
Pansy 5.5-6.5
Peony 6.0-7.5
Petunia 6.0-7.5
Phlox, summer 6.0-8.0
Poppy, oriental 6.0-7.5
Rose, hybrid tea 5.5-7.0
Rose, rugosa 6.0-7.0
Snapdragon 5.5-7.0
Sunflower 6.0-7.5
Tulip 6.0-7.0
Zinnia 5.5-7.0


Related Articles


this is going to be sweet

By Tega Komori

this is going to be sweet

Last autumn I applied dried

By craig killy

Last autumn I applied dried chicken manure (25 oz. over 30 sq. ft.) to my garden and worked it in w/compost I than put a ground cover of leaves over the winter. I intend to grow vegetables i.e. Tomatos, Beans, and some flowers. Will my soil be too sour and if so what can can I apply to counteract the effects?

Hi, Craig, that sounds like

By Almanac Staff

Hi, Craig, that sounds like an enviable mix. Kudos! As for the pH, this is a different matter. Get yourself a test kit at a nursery or garden supply store (they are relatively inexpensive at a couple of dollars or even less) and check your garden. We would not want to hazard a guess at the current pH; best to know for sure.

Tomatoes like a pH of 5.5 to 7.5 and beans, being companions to tomatoes, generally like it about the same (6.0 to 7.5). Flowers can vary a bit but most are in the same range. See here for details:

Ok so I just added compost

By Cole Fisher

Ok so I just added compost manure to the garden for when i plant the rest of my fall vegetables. Can I plant them in the soil the same week that I added my compost? will the compost harm them or should I wait a little while before planting them?

As long as you have worked

By Almanac Staff

As long as you have worked the compost into your soil, there is no reason to delay planting.

Folks.....there is some bad

By Lance Jones

Folks.....there is some bad news out there. Check out on YouTube "What in the World Are They Spraying?" Or...."Look Up".

We are being bombarded by "Chemtrails" (Geo-Engineering") which is making our souls turn alkaline. I have lost almost all my valley Locust Trees, the Oregon Grape isn't happy and don't know why the Pines are dying. Nobody hardly knows. Look into it......we have to stop this! Planes fly over leaving white stripes that spread out and cover our skies.....leaving aluminum, barium and strontium (reports even of flouride) in out soil and water. Spread the word, tell your government to STOP!! Its global.....sinister. They say its for Global warming, but it actually keeps the heat at night like a blanket. Monsanto has applied for a patent of Aluminum and Drought resistant seeds. They are manipulating the weather! Sorry for the bad news.....

Thank you for the post! Yet

By suzanne h.

Thank you for the post! Yet another worry. I have walked through patches of clover, planted organic comphrey and herbs which flower heavily all summer AND NOT ONE HONEY BEE! Only a few bumble bees...and no wasps, either. Three years ago there were handfuls of them. When I was a kid, the clover was alive with honey bees. If everyone could just take a second and notice what is happening. Something is terribly wrong right now.

sorry for the typos and the

By Lance Jones

sorry for the typos and the news....SOILS are turning alkaline. Let me know if anyone is aware of this! Our young black locust trees are all dead in ONE YEAR.... not one leaf. And the older ones barely have any leaves and they have been here for many many years, always healthy. Bumbles bees have been coming here for over 20 years. I did research and Black Locusts are highly sensitive to ALUMINUM! Greenhouses are now a very good idea....I just hope the Pines aren't dying from this too. They like acid soils....???? This is here in NE Washington.

hi ther have done a ph test

By nathan2011

hi ther have done a ph test to my soil an its come back at 7.0 an other places on the plot are 6.5 i have some veg that is between 6.0 an 7.0 wich area would i be best to plant them in higher end of plants ph or the lower end of ther ph for the best yield

In Oct. I placed my own

By Kathy T.

In Oct. I placed my own composit on my Raspberry plants. Then in Nov, spread some pine needles on the bed. I have some Manure in a bag from the store. Would it be safe to spread a little of that also? I have had a decrease in my rasp. production in the last few years so I have been trying to figure out what the cause is. I would appreciate any help. Also how can I have the soil tested?

well I put fresh manure in my

By charlie russell

well I put fresh manure in my compost but this manure you got its already composted if your not sour how munch manure to put around your plants send me an e-mail and if you got any questions on composting ask me my e- mail address is if you don't have an e-mail address well just reply

Hi My garden soil is very

By Wessie van der Westhuizen

My garden soil is very sweet.
I want to plant Prorea plants which need a sour soil.
What can I do to change my garden soil to be sour?

Your assistance will be appreciated.


You can use a proper mixture

By Brandon Schulte

You can use a proper mixture of white vinegar and water to boost the acidity of your soil or you can add pure sphagnum peat which has a very low ph. Blueberry bushes thrive in low ph and are suggested to be planted in pure peat. So this should remedy you ph issue for raspberry bushes..

Coffee grounds, pee on the

By Jeremiahiii

Coffee grounds, pee on the soil (not the plant), manure from a city horse farm would be good. Sulfer if you want to buy something.

You can usually get a soil

By Almanac Staff

You can usually get a soil test kit from your local county extension office, and they will recommend any amendments that your soil may need. Wait to add the manure until you get the results from the soil test. Also make sure that your raspberries are not too crowded. You may need to prune out some of the old plants.

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