Now, there are plants (including some veggies) that seem to be immune, or at least relatively unresponsive, to the effects of juglone. These plants include carrots, corn, squashes, beans and melons. I'm sure there are more, but these are the common veggies. You could try growing those plants, but I do think the raised bed issue will give you some success as well. Normally growing plants that are susceptible to the effects of juglone outside of the drip line (the drip line is the area on the ground directly underneath a tree's canopy) will not result in their succumbing to the effects, but walnuts' roots can grow past the perimeter of the drip line as well. I hope this information has been helpful. Let me know if you have any other questions. Cheers...Dr. Robby

Being vigilant with the removal of walnut tree litter from your raised beds is important too. Granted the roots do produce more juglone than any other part of the walnut tree, but there is still some in the leaves. When the leaves decompose, it releases the juglone into the soil. This is also why you shouldn't use walnut leaves for composting.

The reason why I say you might be able to get away with raised beds is how the juglone gets into the soil. Juglone is found in almost all tissues of the plant: leaves, bark, wood, roots. The roots, however, produce more juglone than in other plant tissues. Not only do the roots exude the compound, but the compound is also released into the soil when the roots decompose. A raised bed will work if a couple of things happen: (1) the walnut roots do not invade the raised bed, (2) and you are vigilant with removing any dropped walnut leaves that may find their way into your raised bed. I would recommend laying down a few layers of chicken wire before you fill the raised bed with soil. This will prevent moles and gophers from chewing on any veggie roots you plant in the bed. This may also stymie (for a short period of time) some walnut root development into the raised bed. Normally tree roots grow horizontally and down, but they will also grow towards moisture, which I assume your raised beds would be leaking into the native soil. Speaking of native soil, do not use soil from your yard to fill in the raised beds. You will have to bring in new soil to fill the raised beds because you want to be sure there is no juglone in it. Juglone will break down when exposed to the air or microbial digestion within 1 month or so, but walnut roots that have yet to fully decompose can provide a steady source of juglone for a long time as the root itself breaks down.

Hey Patricia...You might be able to get away with growing veggies around your black walnut trees by using raised beds. Let me tell you how black walnuts cause other plants to wilt and die though. Black walnut is a member of the plant genus Juglans. In this genus you will find a number of plants that produce a compound called juglone. This compound is a known plant growth inhibitor and has been used as a natural herbicide. Tomatoes and peppers are both susceptible to juglone's toxicity. The compound is more or less harmless to people, but some will say that the allergic response to walnut pollen is greater than other plants' pollens.

No problem at all. I appreciate your kind words. :)

I hope this is helpful. Let me know if you have any further questions. Cheers...Dr. Robby

Now here's the kicker: plants are sacrificing some sugars to the fungi for the fungal services, but what happens if the nutrients are not in any deficiency in the soil. In other words, what if you as the gardener are capable of constantly providing enough nutrients to the soil so that the plant is never really lacking. In this scenario, a plant that has a mutualistic relationship with a mycorrhizal fungus is now sacrificing sugar that could be used to make new plant parts to the fungus for no added benefit. This is generally the case for plants grown in pots. Mycorrhizal fungi will give the greatest benefit to plants living in the ground and not in pots. This makes sense when you think about it though. The mycorrhizae help the plant explore the soil for nutrients. When a plant is in a pot, the roots cannot really explore much and the nutrients generally have to be provided to them.

Hey Christopher...Mycorrhizae are fungi that form a symbiotic relationship with many, many plants. There are three main types: Ericoid mycorrhyzae, endo-, and ectomycorrhizae. Ecologically speaking, a mutualistic relationship means that both parties will benefit. In this case the fungi will get sugars from the plant and the plant will get more nutrients (usually phosphorus) from the fungi. These fungi associate themselves with the plants roots and will essentially increase the surface area that the roots are exposed to the soil. In addition, the fungi have a few tricks up their sleeves to make nutrients more available for absorption. You can inoculate your soil with these fungal spores, but they more or less are found naturally in nature. Many plants cannot thrive without them now. In fact acid rain has a detrimental effect on the growth and infection rate of these mycorrhizae and many scientists feel that trees suffer more from lack of mycorrhizal infection than from the acid rain itself.

Hey Christopher...There are many organic ways to control pests. There are also some non-toxic sprays that you can use to control pests. Horticultural oils and pesticides with potassium salts are generally safe to use on plants that are meant for consumption. (BE SURE TO READ THE INSTRUCTIONS OF ANY PESTICIDE SINCE MANY OF THEM ALSO HAVE CHEMICALS IN THEM THAT ARE BAD FOR HUMAN CONSUMPTION.) You can also introduce some predatory insects to your garden. The most famous of these are lady bugs. Lady bugs are voracious predators of aphids, but they can sometimes simply fly away when you introduce them to your garden. As for eradication/genocide vs. control, it is almost always impossible to eradicate the pests from your garden. For the most part, the best you can hope for is to maintain a low population of pests. You can achieve this naturally by growing leafy perennials around your garden. This is a good place for natural pest predators to lay in wait so they can prey upon your pests when the pest population increases. Growing carrots (although not a perennial) is a great way to introduce natural predators to your garden. Carrots and plants in the same family as carrots generally have highly dissected leaves which give great hiding spots for predators. If you want quick results I would recommend using a non-toxic pesticide, but if it's a sustained predator population you're after, you may want to look into predator introductions and growing plants that will naturally host them. I hope this is helpful. Let me know if you have any other questions. Cheers, Dr. Robby

Hey Eric...By chance do you know what cold hardiness zone you are in? Moringas do best in zones 9 through 10. Also, they can easily be overwatered. They prefer dry, sandy, well-drained soils. Chances are you may be overwatering your Moringa. If you are questioning whether or not to water, I would suggest you let the soil dry out a bit further. In fact you can let your Moringa dry out enough that you let the tree let you know when it's time to water by when its leaves start to wilt slightly. That would be my best guess of what is going wrong right now: overwatering. Let me know if you don't think that is the case and we'll try to get down to the bottom of this. Cheers...Dr. Robby