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Another basil question

What' might be causing the new leaves on my basil plants to be turning almost a yellowish-green? Thanks!

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    1. sunburn? esp when to dry. also water on the leaves when the sun is out..

      1. Not getting enough nutrients from the soil. I've never had that problem, so I don't know what to recommend, but I suspect they are planted in poor soil.

        If they are in potting soil, then perhaps sunburn. In warm climates they can take a fair amount of shade, esp. in the afternoon. They have big leaves which tend to burn.

        1. Stress.

          Are they in the ground or in a planter?

          How often do you water them.

          Soil makeup?

          How much light per day?

          I;ve seen far more yellow leaveswhen I try and contariner garden basil or short them of req's daylight/sun.

          I;ve got 3 basil bushes going now but have been on the other side.
          Not fun so I understand.

          1. Best guess is lack of nutrients as mentioned. When did you last fertilize?

            1. Thanks for all of your helpful insights. I'll try to respond to all of your guesses/suggestions. Then we'll see what remains.

              My basil is planted in a small (2' x 4') raised bed (about 30" high) that sits on my back deck. I filled the bed with new Miracle-Gro potting soil before I did any planting this season. The bed gets about 3-4 hours of direct sunlight each day, from late morning to early afternoon. I haven't really had to water too much this season because we've had a fair amount of rain. The potting soil has "moisture control," so it retains some amount of moisture. And the bed has good drainage when I do water or if we have heavy rain.

              I used the same bed last summer and my basil grew beautifully. FWIW, I live in southeastern PA, and although we've had a few days with temps in the 90's, we haven't had "scorching" weather yet this summer.

              As for nutrients in the soil -- well, I haven't added anything because the Miracle-Gro has fertilizer in it. When I use Miracle-Gro, I usually add fertilizer after a couple of months, so it seemed a little too early to supplement what came in the soil.

              Where do I go from here?

              4 Replies
              1. re: CindyJ

                Here's a good short article from Mother Earth. Important here is to remove the affected leaves. If it's a fungus it will spread to the rest of the plant.

                It could be as easy as how you water as explained here. Basil and tomatoes (and probably lots of other veg plants) can get leaf diseases if you water from above, which we often do.

                If you planted in a Miracle Gro potting soil I don't think you would need to fertilize it. I grow all organic and only use manure tea for fertilizing edibles but I do use potting soils for annuals, etc. and might do one additional fertilizing during the season.

                It sounds more like a fungus to me.


                1. re: sandiasingh

                  I don't really have spotting, and I haven't seen any of the other signs of fungus described in that article ("...gray, purple or white fuzz.")

                  The problem might be the way I've watered the plants on those rare occasions when I've actually watered. I typically water the soil using the "shower" setting on the hose, but then I give the leaves a "drink" with the "mist" setting. I do my watering in early morning or late afternoon.

                2. re: CindyJ

                  FWIW, this is from the site Dave's Garden albeit from 2000. I doubt things have gotten better.

                  "And there’s more: long-term studies at the University of Wisconsin have shown that acidic chemical fertilizers are causing serious, permanent damage to our soils. Usually these fertilizers are also highly soluble, so they leach away and pollute our water systems, too. Soil fertility authority Garn Wallace, Ph.D., of Wallace Laboratories in El Segundo, California, points out that Miracle-Gro contains muriate of potash, which contains excess chlorine that will burn plants and inhibit the uptake of nitrogen. Dr. Wallace also warns that products such as Miracle-Gro often contain unsafe levels of zinc and copper that will be toxic to soil life."

                  Read more: http://davesgarden.com/guides/terms/g...

                  1. re: gourmanda

                    WOW! It's too late for me to replace the soil this year because I've got many other herbs growing pretty well in the same bed. But I've been using the Square Foot Gardening system of planting, even though I have only 8SF. I think I'll go with Mel's Mix for next year.

                3. Cindy J, I;ve been growing basil in teh same spot for almost a decade, replenishing the soil every year and adding manure, compost and turning.

                  I also used Miaracle Grow in very light doses for that duration with no ill effects.

                  Hell, I use it now.

                  If the lower leaves are yellow and the rest of teh plant fine, I'm still betting on lack of proper sunlight and too cold of days and nights.

                  In the fall, I get yellow lower leaves when the evening get cold.

                  In the summer, I get lower yellow leaves when moisture swings a lot due to mainly drought. My soil drains so well I nver fear of overwatering.

                  When i tried to container basil at my old house with limited sunlight, it failed miserably. Too littel light and wild swing in soil moisture due to summer heat.

                  I only do sweet Genovese basil, , and some plant can be a little fussy at the start as this year proved to me.

                  Now the basil triplets are up to 24" high (60cm) and need weekly trimming. (See pics-one from first of June and big pic is from last week)Same three plants from this year in same places in both pics.

                  Again, manure and very light Miaracle Gro for fert. and sun from 6am to 3pm.

                  No yellow leaves for me and I;m the next state west of ya. :-)

                  Keep monitoring and report back.

                  1 Reply
                  1. re: jjjrfoodie

                    Now I've got a bad case of basil envy!

                  2. I'd suggest getting a soil test done at your local Extension. If the pH is off, all the nutrients in the world won't help.
                    Here's an article that may be useful:


                    1. When you say "raised bed", I am thinking in the ground, but it sounds like you mean planters ( not in "dirt" that is connected with the earth). Is that so? How do they drain? Does it pour out of the bottom, onto the deck, at the same rate it goes in? Does excess water sut in a reservoir?

                      Also,a picture would help alot.

                      8 Replies
                      1. re: Shrinkrap

                        It's a raised bed, although the dirt is not connected with the earth. The photos show the yellow splotches on the basil and the raised bed that is my herb garden.

                        1. re: CindyJ

                          Ohhhhh! They look pretty good to me! Are they self-watering? Can you describe the drainage?

                          I have about 10 or so on my deck. The planters watered from the bottom need less feeding than those I water from the top.

                          My basil.

                          1. re: Shrinkrap

                            The bottom of the bed is wooden slats with small spaces between them. The bottom and sides are lined with some kind of cloth that came with the bed to prevent the soil from running out. No, it's not self-watering; I water it as needed, which hasn't been too often, given the rain we've had over the past several weeks.

                            You have 10 of these beds on your deck?

                            1. re: CindyJ

                              I have ten what I would call "planters" on my deck. Actually about 12. Five from "gardeners supply", 7 "earth boxes". Are those from "gardeners supply"?

                              In any case, to me, they are more like "container gardening", than "raised bed gardening". They require more attention to watering and feeding. How do you decide when to water? How much "mix" do they hold?

                              1. re: Shrinkrap

                                I really like this planter box. I'm not much into gardening, but I do appreciate having fresh herbs, so this small setup works well for me. The Miracle Gro potting soil seems to retain moisture pretty well. I water when the soil feels dry. How much mix -- I think I used two large bags to fill the bed. It's 2' x 4' x 10" deep, so if I fill it to a depth of 6" that would be about 4 cu. ft. of soil. It's made by a company called Gronomics and they're available in a few different sizes. I really like the 30" height -- for planting AND harvesting. And weeds are non-existent.

                                1. re: CindyJ

                                  Nice! I love my planters too, although only self watering works for me. We get virtually NO rain from about May to October, and many days between 90 and 105.

                                  Any chance it could be TOO wet? When you check the soil, how deep are you checking?

                                  1. re: Shrinkrap

                                    There's nothing scientific about the way I check the soil. It's a combination of how it feels, how hot it's been and how recently we've had substantial rain. We've had one or two BIG rainstorms every week for the past few weeks. And if the planter box is too wet because of rainfall -- oh, well... not much I can do about that.

                          2. re: CindyJ

                            It could be as simple as adding a little iron to the soil. But all that rain you mention could be an issue, too. Might be washing the nutrients right out of the box.

                        2. Hi CindyJ-

                          I left our Basil starts alone for over one month, and we returned (World Cup) to find that our battery-powered drip system worked. Our eldest son came by and thoughtfully removed the plastic wrap covers I had put over the starts when the weather warmed up, and the sprouts started showing.

                          We have experienced the condition you mentioned in past years. It could be the collective abundance of watering, especially if the soil mix included water retention "beads", and then again it could be a fungus.

                          Note that we buy our seeds from a supplier in Genoa, Italy, and try and give them a hot, " Italian-like " environment in the Summer. As a rule we always clip off the lower leaves of our growing Basil plants 3 inches or more above the soil, which improves the air flow around the plant stalk. That can reduce some mold sporalization, which if the plant is in a humid location can cause problems.

                          1 Reply
                          1. re: SWISSAIRE

                            I've never had much luck starting basil from seed, and there was one year when I even bought a couple of varieties of basil seed from Italy.

                            That's interesting how you clip off the lower leaves. They're not usually good for eating anyway, and giving the primary stems more air flow makes a lot of sense. Thanks for the tip.

                          2. In my experience I have to use (pluck) basil daily, or at least every other day, during summer growing season.

                            We were out of town this past weekend and I notice that some of the lower leaves are "yellowish". I've pinched off the tops and will use the leaves on pizza this weekend.

                            Crossing my fingers that the sun-deprived leaves will sally forth in the next week or two....

                            Basil is interesting in that it BEGS to be harvested and used. The more I use it, the more prolific it seems. If only I can get my VISA account to follow suit....

                            1 Reply
                            1. re: pedalfaster

                              Beat you to it.

                              Made a White Pizza with shrimp, capers, a handful of fresh basil, and cheese for dinner Friday night, a few hours ago. A good Sauvignon Blanc, and a salad. Great !