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Yellowing Aster

    Date Posted: Wed, Aug 18 - 1:46 pm

    Question

  • Hi we have a row of fall aster and notice that this year and last as the rest of the plant grows large and bushy the base starts to get yellow and then dries. the plant seems to be getting enough water. Is this normal?
  • Answer

  • Good morning, and thank you for your question! My first thought is that you may have a watering issue. I’m assuming your aster plants otherwise have normal growth, are not stunted, and bloom well. Asters do prefer well-draining soil and like to keep well watered. However, they do not like overhead watering or sprinkling. Doing so can result in development of a fungal disease. Watering should be done at the base of the plant where fungus would first develop. It also helps to use a good organic mulch around your aster plants to help retain moisture and prevent splash to the lower leaves which can cause the yellowing. As a side note, be on the lookout for leafhoppers on your aster. They can spread bacterial disease (phytoplasma), which is a more serious problem to deal with, but with this you would likely notice other symptoms such as stunted growth and deformed flowers as well. If those symptoms develop, the plants would need to be removed as there is no cure. It does not sound like you are experiencing these specific problems with your aster, and proper watering and mulching would be the best first steps to implement. Good luck with this, and let us know if further symptoms develop.

Eradicating Giant Taro

    Date Posted: Wed, Aug 18 - 1:43 pm

    Question

  • Continuing along the theme of invasive species, we have several clumps of elephant ears (giant taro) in our yard that we are trying to eradicate. We have dug them up twice already and they keep coming back. Any tips or solutions that can rid of us of this invasive plant? Thank you very much.
  • Answer

  • Good morning, and thank you for your question! Giant Taro (elephant ear) are dramatic and beautiful to admire, but we know they can be problematic spreaders. This invasive plant is typically hardy only in zones 8-11, but with our recent mild winters here in zone 7, they easily thrive. They are best planted in very large pots in the garden or on the patio, where they can be contained and enjoyed without the spread. The best organic approach for removal and eradication of elephant ear in the garden is to simply dig them up (and likely repeatedly), until they are all gone. It sounds like you’ve taken this approach twice and they’ve come back. Be sure and dig wide and deep enough to remove all small pieces of the corms (tubers), and dispose of them in a plastic garbage bag. These small pieces can colonize and form new plants if left in the ground. Remove the soil in the area and replace it as well. As you’ve learned, this often requires repetition until they are all gone. If any new growth emerges during the fall, repeat the process, cutting down all growth to 1” above the ground and dig up the tubers and all small corm pieces in the ground before winter. I wish I had more magic tricks for you to try to solve this. Perhaps we’ll have a colder winter this year (more in line with our climate zone) which will help as well. Good luck!

Shasta Daisy-browning, die back

    Date Posted: Tue, Aug 17 - 8:52 pm

    Question

  • I have a large shasta daisy that I planted along my side yard years ago. About 3 years ago it started having "issues". It starts the spring with very green and abundant stems/leaves. And everything seems wonderful as the plant starts to bud....but then the flowers bloom already browning and die quickly. I am guessing it has some kind of wilt but not sure what to do. I also have dianthus in pots up my steps for the first time and it appeared that they also caught "the wilt" but they seem to be bouncing back. Not so for my Shasta daisies. Is there anything I can spray them with or can I transplant? It's such a gorgeous prolific plant.
  • Answer

  • Sorry to hear of your daisy troubles. I'm going to refer to a previous answer I gave about Rudbeckia 'Goldsturm'. The daisies are also one of the stalwarts of the garden but can run into various problems. Please see the rudbeckia answer below. I didn't spell it out in the answer below but good drainage and air circulation are essential for plant growth and prevention of fungal diseases. And again, if your plants continue to succumb, selection of a new plant for your particular environment may be a good solution. Good luck, let us know your progress! "Rudbeckias are usually pretty sturdy plants but they do succumb to some fungal issues. Sometimes the problem could be attributed to too much water, so that's a simple fix. Or, you may be dealing with septoria leaf spot or a similar fungus. Rain and humidity contribute to the problem. You can start with some cultural practices. Remove all affected leaves and put them in the trash. The fungus overwinters in infected plant debris so you want to clean up the area around the plants to make them less inviting to the fungus. You may also try moving the plants to a spot with new soil and seeing if the plants improve over time. Additionally, do not water from overhead. Try a soaker hose so that the foliage does not get wet. You could also try a baking soda solution spray but that's usually better at prevention. A neem oil solution may be effective. You may decide to simply remove them from the garden and substitute another perennial that's less susceptible. There are many choices. A lot of gardening is just adapting to your circumstances and trying new plants that may be better suited to your patch of ground. Best of luck with your garden! "

Rudbeckia-leaves blackened

    Date Posted: Tue, Aug 17 - 8:51 pm

    Question

  • I’m having a problem with my Rudbeckia Goldstrum. The leaves are blackening and the plants dry out and die. I took pictures but can’t figure out how to attach them to this message. So far the problem is only with the Rudbeckia.
  • Answer

  • Hello there, Rudbeckias are usually pretty sturdy plants but they do succumb to some fungal issues. Sometimes the problem could be attributed to too much water, so that's a simple fix. Or, you may be dealing with septoria leaf spot or a similar fungus. Rain and humidity contribute to the problem. You can start with some cultural practices. Remove all affected leaves and put them in the trash. The fungus overwinters in infected plant debris so you want to clean up the area around the plants to make them less inviting to the fungus. You may also try moving the plants to a spot with new soil and seeing if the plants improve over time. Additionally, do not water from overhead. Try a soaker hose so that the foliage does not get wet. You could also try a baking soda solution spray but that's usually better at prevention. A neem oil solution may be effective. You may decide to simply remove them from the garden and substitute another perennial that's less susceptible. There are many choices. A lot of gardening is just adapting to your circumstances and trying new plants that may be better suited to your patch of ground. Best of luck with your garden!

Lavender siting, growing

    Date Posted: Tue, Aug 17 - 8:42 pm

    Question

  • I have 3 small (6 " high) lavender plants. Where is the best place to plant? Do the roots get deep/wide? How long will it take for them to get 2 feet tall? Any best practices? Thank you.
  • Answer

  • Hello there, lavender is a lovely plant and generally not fussy if given the right conditions. It's partial to warm and dry, not so fond of humidity, but if you plant it in area with good air circulation that should help. Also, it needs well-draining soil, no compacted clay for this plant. As far as height and growth, without knowing the cultivar it's hard to say but it will probably put on a couple of inches of growth each year and most varieties are in the 2-3 foot height at maturity. Enjoy the fragrance!

Raised beds - yellowing leaves

    Date Posted: Tue, Aug 17 - 8:41 pm

    Question

  • I created new raised beds and filled them with Miracle Grow Raised Bed soil combined with mushroom compost. All of my plants have yellow leaves. The soil should be provided the necessary nutrients, and I was wondering if the weather might be part of it? Can you give me an idea of what I should do? Thank you
  • Answer

  • Hello - interesting question. The first thing that comes to mind is your soil. It sounds like you have created a very rich soil for your new plants. Typically, yellowing leaves can indicate a nutrient deficiency, and/or the soil is too wet. As you know, mushroom compost does a good job of soaking up a lot of water and helps keep soil moist. It is also nutrient-rich, and contains a high degree of soluble salts. I’m wondering if your ratio of mushroom compost to soil is too high. The mushroom compost should make up about 1/4 of the total volume of the soil. If your soil is too concentrated and the plants are seedlings or are very young, this may result in your plants dying. The soil may actually be too rich for them. Also make sure your soil is not staying too wet. It should be allowed to dry before adding water. Good luck, and let us know if we can help further!

Majesty Palm dying

    Date Posted: Tue, Aug 17 - 8:40 pm

    Question

  • I have a majesty palm that sits in a corner by my living room windows. It doesn't get very much light there (but I don't have anywhere else to put it) so I added a growth light. The light delivers red and blue light for 4/hrs every night and is set up about 5 feet away. I also have a terracotta automatic water in the soil, which keeps the soil most without being soggy. Nonetheless, the plant is dying. The fronds have been turning brown from the outside in and now I've had to cut away two complete fronds which and a third is on the verge of death. What am I doing wrong and is there anything I can do to still save it?
  • Answer

  • Majesty palms are very particular about the level of light required, but it sounds like you are dealing with that effectively with the grow light. One factor you did not mention was your soil. These plants require very well aerated, loose soil which drains well. Make sure your soil is not too dense, particularly since you are irrigating with terra-cotta automatic watering. I have three majesty palms and all are sitting in north facing windows. They are getting only indirect light all day. One of them was initially in densely packed soil, and was not doing well, so I repotted in a very loose soil and the palm seems much happier. Also, these plants love to be fed. I use a miracle-gro continuous release palm plant food, so you may want to try that.

Tomato-Blossom End Rot

    Date Posted: Tue, Aug 17 - 8:37 pm

    Question

  • I'm just starting to see fruit on my tomato vines, but unfortunately they look to already be developing blossom end rot. I'm using a mixture of organic soil with fertilizer and perlite, and I'm not sure if the plant is salvageable. What can I do to help this plant? And what advice can you give for other tomato plants to prevent this blossom end rot? Is there something I can apply early on to prevent this? Thanks!
  • Answer

  • Hello there, This is a pretty standard issue with tomatoes. Generally, the cause is inconsistent watering and/or a calcium deficiency. So the first step would be to establish a consistent level of watering for your plants. Of course, Mother Nature plays a role here as well, you can't control that. If you're sure that watering is not the problem, then you need to think about calcium. Without testing the soil you won't know the level of deficiency. But if you want to proceed, there is a short-term fix. I haven't tried this myself because the cause for me was generally a watering issue, but you can spray the plant with a calcium solution. That will buy you some time to increase the calcium content in your soil. There may be enough calcium in the soil but the ph of the soil may be preventing the plant from absorbing it. I don't understand all the chemistry of this but soil ph is the root of plant happiness. A ph of around 6.5 will do. Try adding some fast-acting lime (don't use dolomitic lime) and working that into the soil about 12 inches deep.The lime frees up the calcium from the soil. As I said previously about chemistry....This is a time-honored practice so it should work for you if, in fact, you find that watering is not the problem. If you would like to have a soil profile done, please let us know and we can send you a soil test request kit. Good luck with the tomato harvest!

Boxwood with patches of brown leaves

    Date Posted: Tue, Aug 17 - 8:35 pm

    Question

  • I just bought a house and I have a boxwood bush in the front that has patches of brown leaves. Is this that blight that I've heard people talking about? would it be a good idea to remove the bush or is there something I can do?
  • Answer

  • Thanks for your question. This does sound like it could potentially be boxwood blight which is a fungal disease, and for which there is no cure. This disease first appears as lesions with dark brown edges on the leaves and black streaking on the stems. The foliage then turns brown and falls off. Observe the leaves and stems on your boxwood for these signs. If your plant is minimally affected, you can cut off affected branches, clean up debris from the ground, bag the trimmings, and put in the trash (do not compost). You may then be able to keep the disease at bay by spraying a chlorothalonil-containing fungicide every 7-14 days. Be sure and sanitize your garden tools with a 1:9 bleach to water solution to avoid spreading the disease. If your boxwood is heavily infected and unsightly, it may be easiest and safest in the long run to remove the whole plant. It’s also important to know that the spores from the infected plant can remain in the soil for 5-6 years, so if you want a replacement plant be sure and select a boxwood cultivar with a high level of resistance which will not require a fungicide treatment.

Dog-proof ground cover

    Date Posted: Fri, Aug 06 - 7:11 pm

    Question

  • Hi! We have a small back yard (no trees) in the Museum District that faces southeast. It's mostly dirt and crabgrass. We also have two dogs. Can you recommend a good, tough, affordable, relatively "dog-proof" ground cover? Something relatively soft that will be okay for bare feet would be idea, if I'm not asking for too much. Thank you!
  • Answer

  • Ok, we'll have to laser focus to meet the requirements. I think a planting of dutch clover might do the trick for you. You're probably familiar with it, it tends to pop up in lawns frequently. You're going to have to kill the crabgrass before you attempt anything else. I generally suggest covering the area with tarps, newspaper, and/or cardboard to smother the weeds. However, this process could take a couple of months and you want to plant the clover about 6 weeks before a frost. If your space is small you could remove the weeds by hand, that would be quicker. Throw the pulled weeds in the trash, you don't want weed seeds winding up in your new clean space. Till the earth you've just cleaned up and spread the seed! Next-water. The clover will sprout in about 2 weeks. You'll need to keep the seed bed moist. Once the clover goes through a winter it will be established. Then you want to weed whack or mow the clover once a month when it's actively growing to keep the planting nice and thick. This choice would be the most cost-effective way to establish a walkable ground cover. An added benefit of clover is that is adds nitrogen to your soil. Of course, there are many other interesting choices for a sunny ground cover. You might want to experiment adding other plants and creating a bit of embroidery. There's always scotch or irish moss, mazus, ajuga, speedwell, or even creeping thyme, to name just a few other possibilities. Good luck with the project!