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Plants needing alkaline soil
in Plants
Are there any plants which actively NEED alkaline soil? I was led to think about this by a post a couple of weeks ago which described some plants as "acid haters".
Having gardened on alkaline, acid and neutral soils, I doubt if such plants exist. Clearly there are plants which can't thrive in alkaline soils, but in my last garden (max pH of 6) I grew numerous things which are said to prefer alkaline conditions (like lilac, dianthus and lavender) with no bother.
I suspect that what these plants wouldn't like is poor drainage and wet winters, conditions often associated with acid soils, rather than the lack of lime.
Am I wrong? Do you have any examples of "acid hating" plants?
Having gardened on alkaline, acid and neutral soils, I doubt if such plants exist. Clearly there are plants which can't thrive in alkaline soils, but in my last garden (max pH of 6) I grew numerous things which are said to prefer alkaline conditions (like lilac, dianthus and lavender) with no bother.
I suspect that what these plants wouldn't like is poor drainage and wet winters, conditions often associated with acid soils, rather than the lack of lime.
Am I wrong? Do you have any examples of "acid hating" plants?
Since 2019 I've lived in east Clare, in the west of Ireland.
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Very acid soil can inhibit nutrient/mineral uptake from the soil as much as very alkaline can so it’s perhaps more where a plant sits on a scale of tolerance rather than acid/alkaline hating or loving per se.
The root stock used for most of Europe’s roses is tolerant of alkaline soil, but they still need an iron boost here because of my water.
Wild shrubs and flowers of the brassica and cistus families certainly grow abundantly around here, plus many leguminous species, which, now I recall, also like alkaline conditions. Calcicole is a term I hadn’t heard of @Loxley, but makes sense. It’s rocky, alkaline clay around here though, not chalk, but plants are similarly adapted/have made it their niche.
@Loxley - I can see how some plants can overcome competition by occupying a niche (such as on chalk, as you say) where they will grow and others won't. If the chalk downland is "improved" (horrible term!) by adding fertilisers they then can't compete, particularly with grasses. But if I plant a Pulsatilla, say, in somewhat acid soil in my garden, removing competition from other plants, will it not grow?
Wild plants will inevitably die out if they are out-competed by others more adapted to the local conditions... but does that mean they are intolerant of any other soil pH, or is there more going on than this?
This page on the RHS website is informative - https://www.rhs.org.uk/Advice/profile?PID=763
I'm still left with the question, @Obelixx - what exactly is meant by a plant "needing" alkaline soil? I understand about ericaceous plants not being able to access iron when planted in alkaline soils, and therefore needing neutral to acid conditions, but what actually happens to a lavender planted in acid soil? I suspect there must be lots of micro-nutrients and trace thingummies it can't make use of as it should.
I'm sure you're all correct though, in saying that the physical characteristics of the soil are at least as important as the pH.
Thanks for helping me to think about it!
Lilac hasn't flowered for two years and that changed after I sprinkled some lime granules around. But it always has been vigorous and healthy looking.
Brassicas are unhappy but that could be also because my soil is too loose and they need it firmer. Smaller brassicas (various salad leaves) are ok.
I've always assumed I can't grow gypsophila... just from the name.