almost any thing, young walnuts will not throw much shade . even as they grow older as long as they are well spaced they have a very open canopy so any thing that should grow in shade should grow for you .and despite the folk-law and chemistry that says things should not or will not grow under walnut trees we are on walnut st with a farm full of walnut trees with grass weeds and flowers growing right up to the trees .
I would start by trying beets , chard,lettuce,green onions , radish ,or hosta ! (which I just found out are edible) for deeper shade .
we have 1 baby walnut ( baby being about 10 years and about 20 feet tall near the veg garden but it is close to the tree line . but on the front lawn my iris sun chokes and butterfly bushes are right under a clump of taller walnuts.
I would start by spending 1 day watching the sun pattern
8-9 in the morning where is the shade ?
chart every hour or 2 where is the shade and is there sun where you want to plant , because the sun moves you may find you are actually getting 2-6 hours sun in the spots you want to plant
and shade is in degrees if the branches are high or low makes a difference ( and some lower branches can be removed on trees with a few years growth )
ours branched fairly high
but even with 1-2 hours sun and a few more hours bright light chard , lettuce , spinach , beets , pac choy and Chinese kale should all grow . they may be less vigorous than those in full sun
I agree with Sue, grow what you want. We have 3 mature black walnuts that shelter around 30 species under them. Service berry, currant, gooseberry, Nanking cherry, Day Lilly, Eastern red cedar, staghorn sumac, Utah Honeysuckle, young apple trees, tulips, iris', mints, etc. etc.
This black walnut covers most of the front yard.
I don't have any walnuts or any other large trees in my garden but I was in France on holiday last month and was fascinated to see how many walnuts were growing there. As well as single trees in open spaces there were lines of them in the hedges which makes me think that I agree with Susan and Bill who have already posted replies. My experience is that green, leafy vegetables and fruit bushes do grow okay in shade. There is one way to see if something works - try it and see. I do a lot of that. If it works, great, and if it doesn't you know to do something else next time!
The problem is that in France walnuts are considered as allelopatic trees!
Not only their shade is particularly deep and cold, but they try to limitate growth of some other plants. Is it through the chemistry of their leaves?
I do not know if this apply to other trees only or also to veggies etc.
I would anyway use them to plant stuff that are supposed to grow in a colder climate than yours,
...and then the short common answer to try hehe.... this answer is always true! Almost
Xisca - pics! Dry subtropical Mediterranean - My project However loud I tell it, this is never a truth, only my experience...
I agree with Xisca. I've read that walnuts give off toxins into the surrounding soil to prevent competition of other growth. I grew up in a neighborhood that was built on an old walnut orchard, and English walnuts were our shade trees. We had one black walnut and that one definitely had a strong scent and undergrowth was very limited around it.
"Our body is our garden, our will is our gardener" ~ Leonardo da Vinci
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