redmoss, I take it that the roots of the zucchini are in a comparatively small area and the vine is spreading out. And that you are checking for moisture etc. in the root area. A certain amount of leaf loss like you describe can be quite normal, especially as the plant flowers and sets fruit. I would be concerned about the young leaves. I would look back to two or three weeks ago and see if any cultural or environmental condition occured to account for the change in the plant. Try the garden center or extension service but this time take one healthy young leaf, one young leaf with early symptoms and two or three others that will show the progression of the symptoms. If you do decide to remove the plant, do it carefully and perform a post mortem or 'CSI Plants'. Examine the roots, the stem at ground level and split the stem lengthwise to see if anything has been ambushing your efforts.

"The bottom most leaves of my tomato plants start to yellow and eventually wilt and die." As said by others, that's natural progression. It can be slowed considerably by adequate and appropriately timed fertilization ... at planting time in the planting hole, and then side dressings at first fruit set and subsequently timed applications throughout the season based on whether the plant is determinate or indeterminate. In my opinion, manure tea is not a complete or sufficiently potent fertilizer to prevent nutrient deficiencies that lead to defoliation. "It seems like nothing at first, but as time goes on, it gradually goes higher and higher, usually the leaves turn yellow atleast half way up the plant. So I go from awesome tomato plants to half dead ones in a couple months." First of all, they're probably not "half dead" only half defoliated. If there are no lesions showing on the leaves ... just evenly progressing yellowing ... and no lesions on the stems, then it's probably nitrogen deficiency and the plant is robbing nitrogen from the lower leaves and transfering it to the new growth. "While this only seems to kill one or two plants out of the bunch, it does stop production on atleast half to 2/3rds of the plant." One of two plants in any garden may die and for a variety of reasons. Are you sure the dead plants died from defoliation or maybe from overall failure due to lack of proper nutrition. If the plants are defoliated 2/3 the way up the plant but still put out new growth and set new fruit, then I again surmise the plants are robbing nitrogen from the lower foliage, transfering it to new growth, and dropping the spent leaves. But then again, you haven't said the yellowing is evenly progressing without lesions or blotchy dark spots or speckles. "I will continue to get fruit the whole season, but it does cut my crop down A LOT." Well, once fruit sets and ripens, there will be no more fruit produced BELOW that point on the vine anyway. If you're growing indeterminates, it would pay you to go to a greenhouse and see how the grower manually defoliates the vines below the highest fruit set. I bet his vines will look like a cleaned up version of yours ... nude from the fruitset down in other words. If you're really concerned about maintaining your vines with as much green foliage as possible throughout the growing season: 1) Prepare the planting hole as described in "Earl's Hole Method" or similar. 2) Prune off all lower leaves below the first fruit set and do some maintenance pruning of damaged or deficient leaves throughout the season. 3) Fertilize with a good balanced tomato food worked into the ground 3 - 4 inches deep in the original bed and side dressed atop the ground at first fruit set and again at second fruit set if determinate or about every 4 - 6 weeks throughout the season for indeterminates. 4) Give your plants a booster shot of foliar feed (good balanced professional stuff) whenever you see some paling or yellowing of leaves.

Too much rain or over-watering, which in a container that small would be easy to do. Other possible causes are lack of nutrients - primarily nitrogen. You must feed them regularly. Or being root bound in the pot. That is a big plant for that size container so it could easily be rootbound. Every time you water a plant in a container the nutrients leach out so they must be replaced regularly. When the size of the container is proportional to the plant you don't have that much of an issue. Dave

BahamaDan, it was a while ago and was something a friend gave me to try to greenup my Persian Lime. I'm not sure now but I think it was Peters liquid S.T.E.M. I only needed to use it once and I think it was a chelated micronutrients product. I had tried using a stronger Foliage Pro solution and also a small amount of vinegar for several months but the leaves still stayed very pale green. I gave it a shot of the S.T.E.M. product, at least that is what I think it was, and it finally greened up right away. It might be that the higher dose Foliage Pro finally kicked in too. I don't know. I haven't needed anything extra than a stronger solution of Foliage Pro since. I also use Osmocote Plus during the summer in case there is too much rain that I can't feed with the Foliage Pro with almost every watering. My water pH is a little above 8 usually which does give me problems in the winter when my plants don't get rainwater. I have a couple of citrus trees that seem to need a slightly stronger dose of FP; the Key Lime, Persian Lime, Meyer Lemon, and Kishu come to mind at the moment. Has anyone else noticed also that some citrus trees seem to be more susceptible to scale too? Cara Cara, Nules, Fina sodea mandarin, Vaniglia sanguigno are scale magnets. I just can't keep them at bay even with alternate weekly horticultural oil sprays and soap/alcohol sprays, and even various Bayer with imidicloprid formulations sprays and soil drenches. I must not be giving them the right concentrations. It is hard as the directions are not given for container plants for most of the formulations. If anyone can help me with ridding my trees of scale, I would greatly appreciate it! I also spend hours wiping off each leaf and branch with soap and water or oil, but they seem to come back with a vengeance within the next day or two. They mass along the branches and finally spread to the leaves. I even have controlled the ants that can spread them about. They are the light brown shelled scale. They seem to thrive on my treatments that should be killing them off. Any suggestions to help me? Cory