Thursday, January 31, 2008

Turfgrass for Shade in Brooklyn

This is the Moss Garden at Ryoanji (Peaceful Dragon Temple) in Kyoto, Japan. Moss gardens require years of growth, great care, devotion, and plenty of irrigation, but they are doable. I have been working on one out in East Hampton for a number of years now and patching are beginning to merge.

I have a house in Brooklyn with quite a lot of trees that shade the property. I would like to grow grass on the property. Can you recommend a grass that would thrive in the New York City climate in the shade? Also, I am very intrigued by the Grasspave2 product at -- are you familiar with this product and would you recommend it? It seekms to make for a very hard-wearing but attractive grass surface.

Thanks for writing. This is certainly a question I could go on and on about but I will try and keep my reply brief.

The reason I could go on and on is because at heart I’m really more of an arborist, and my personal love is trees. Trees thrive in a fungal-dominated soil where turf, because grass is a herbaceous plant and not a woody plant, tends to prefer a more bacterial-dominated soil. Mixing the two can be tricky because it’s not as natural a combination as most people like to think. Again, to revert to my arboreal nature, when you take a walk in the woods under established trees you simply do not find turf grasses. So, right off the bat I can say that this might not be the easiest task, but as we have seen here and there people have made it possible to incorporate both trees and turf in a small area.

Before I get to grass options, let’s talk amount of shade. Depending on how large and established the trees are, you want to first think about how much shade you are really dealing with. And without seeing the site this becomes more difficult for me to speak to, so you’ll have to make a few judgment calls. If the area underneath is so shady that right now nothing is growing, except maybe a few weeds, then grass might not be the best option. Proper horticulture is all about the right plant in the right place, and trying to force grass in too shady a location it simply won’t take and you’ll just get frustrated. If some light gets through, what we’d call dappled shade, then that can still be tricky for growing turf grasses. Many ferns as well as shade-tolerant plants like hostas and astilbe, those kinds of plants will do fine in dappled shade and can fill in a space pretty successfully in the course of a couple years. If there are large shadows cast by the trees but otherwise some direct sun hits the ground then turf grasses are perfectly viable.

Scott’s and other large scale gardening companies have made great strides in terms of the products they offer. Scott’s has shade tolerant grass seed mixes that, if the light is dappled shade or better, should take just fine. (I just checked and unfortunately their website is down, but you will see there products in any major retailer or garden center). Not always, but most of the time shade mixes have a combination of ryegrass, fescue, and bluegrass. Ryegrass is incorporated because it germinates quickly and gives you some instant gratification, but ryegrass doesn’t last forever. As it fades, the fescues and the bluegrasses take over. Fescues are great for both their shade and drought tolerance, but take a long time to germinate and get established. Bluegrass used to be more of a sun loving turf grass, but as growers have grown and cultivated new varieties there are more and more shade tolerant bluegrass species on the market every year.

I once wrote an article on alternatives to traditional turf grass species and here is a little excerpt from that as well:
“For turf style grasses in a shady environment turn to the sedges. Catlin sedge, Carex texensis, is a fine, short sedge well suited for partial to full shade. Even though considered to be tolerant of sun, you might find that too much sun will lead to faded foliage and the need for more water. Hardy from zone 6 down to zone 10, this is an excellent choice for hot climates of the south. For the same success in cooler locations, turn to Pennsylvania sedge, Carex pensylvanica. Also a short, fine sedge for shady applications, Pennsylvania sedge is a strong alternative due to its tolerance for a wide range of soils. An amazing characteristic of both these sedges, as passed on by a colleague of mine, is that they only need to be mowed two or three times a year. The third recommendation for this category is the finest textured of the three, Carex senta, or Baltimore sedge. Very similar to Carex texensis, Baltimore sedge performs excellently in shade. For this sedge, however, you may find that it requires more regular mowing than others.”
Sedges you will not find in seed form, but more sold as established plants. I would hope that some local nurseries in Brooklyn sell sedges along with their grasses.

As for that Grasspave product, I am not familiar with it, but based on the reading I have done, I do not think I would recommend it for a situation such as yours. For a larger area where vehicles are being driven often (playing fields, car dealerships, driveways) maybe that system is of benefit, but for a property in Brooklyn I would again focus more on planting the right plant for the right place. Different grasses have different wear tolerance as well as recuperative potential, two phrases you will want to familiarize yourself with more, and if you can find shade tolerant mixes with those additional characteristics you should be fine. Since you are probably going to be dealing most with basic foot traffic I would fear that investing in a product like GrassPave might be a waste of money. Once we figure out the best grass for your property then we can talk about how to best care for it. People can gravitate towards strong chemicals and extremes when simply cutting your grass at the optimal height along with proper fertilizing will help minimize basic wear and tear and allow you to maintain an attractive property.

Wednesday, January 30, 2008

Reminder: Lecture Here at HSNY This Evening 1/30/2008

Lessons in Plant Maintenance: A lecture by Robert Monteleone
Wednesday, January 30, 2008, 6:00 – 7:30pm
Free for members, $10 for nonmembers
A graduate of NYBG’s School of Professional Horticulture, Robert currently operates a rooftop design and maintenance business in New York City. Join him as he speaks about the importance of proper horticultural practices, plant maintenance, and species editing as it pertains to small-space urban gardening.

Friday, January 25, 2008

Help with Drooping Houseplants

All my corn plants look like Quasimodo! How do I straighten them out?

Actually, they might not be corn plants. There is another one that looks very similar which is called a spineless yucca (Yucca elephantipes). Whereas corn plants and other kinds of Dracaena can deal with low light, spineless yucca benefit from bright light with plenty of direct sun. I am going to guess that the reason they have all flopped over is because of water, either an extreme of having too much or having too little. The soil should be kept moist throughout the summer and allowed to only dry out only a little in winter. The one thing, unfortunately, that growers and florists don’t always tell you is that inconsistent watering can lead to these plants drooping pretty seriously pretty quickly. I had one client once who was so attached to hers, as it was her only outdoor plant that survived 9/11, and it devastated me to have to tell her that she needed to start over because the plant had flopped to such a point that I knew it would not stand up on it’s own again. For your situation, apply small quantities of water with regularity; let’s say once a week. Some folks I have talked to also mist their yucca, but that is often more necessary in the summer during warmer weather. Try and find something like a bamboo stake or two and some twine so that you can stake up the flopped portions of your plants. If staking is a new or intimidating endeavor, let me know and I will advise you further.

Plant ID: Begonia sp.

Can you please name this plant? And tell me how to best care for it? Thanks.

The plant in the photographs you have sent is a definitely a kind of begonia. If I had to guess more specifically than that, I might guess that it is a certain cultivar called a ‘Corallina de Lucerna’. There are thousands of different kinds of begonias out there and each one will have one of three different kinds of root systems: fibrous, rhizomatous, or tuberous. Begonia ‘Corallina de Lucerna’ has a fibrous root system, consisting of many fine roots that tangle instead of roots consisting of larger fleshy rhizomes or tubers. Based on that assumption, this is what you need to know about caring for your plant.

Your begonia requires bright light but does not need direct sun. If you wanted to try and get it to flower you would have to increase the sun to the point where the plant is getting about 4 hours of direct sun a day. However, where you have the plant now, if it is under florescent light on a daily basis it should be getting enough full spectrum light to be able to properly photosynthesize. During the summer months you can keep the soil moist on a regular basis, or allow it to go slightly dry between watering, but in the winter you want to water less. The plant is much less active this time of year so you can let the soil go fairly dry between watering. You will want to give it a weak solution of a balanced fertilizer every two weeks during the summer months only, when the plant is getting more sunlight and growing at a faster rate. The only other thing is that begonias love humidity. If you placed a layer of small stones or pebbles in the saucer underneath the pot and let excess water accumulate there, then the water in that “buffer zone” can evaporate and provide some humidity for the plant. As long as the roots are not sitting in water for any length of time, which runs the risk of root rot, the begonia will benefit from the extra moisture in the air. Since our places can get so dry in the winter I might even put a little water solely in my saucers if the plant’s soil is still moist and does not appear to need more water. As far as the container it is in, it should be fine. You could maybe repot it to a container an inch larger in diameter, or maybe even just do a little “top dress” of fresh soil, but hold off on that until spring.

Using the HSNY Library

(The HSNY Library has a number of visual and written publications on a wide range of horticultural subject matter such as this illustration from Orchids from Curtis's Botanical Magazine, Edited by Samuel Sprunger)

I am a journalist writing a story on the orchids of the Yucatan for the AOS. I wonder if I can come down to the HS to use the library for my research. I am especially looking for Eric Hagsater's Orchids of Mexico or similiar volumes.

Yes, you should absolutely come down to the HSNY Library and let us help you. A horticultural library with over 10,000 volumes open to the public M-F from 10-6, the HSNY Library is intended to be a resource for everyone here in the city. I can't say off the top of my head whether we have Eric Hagsater's book, but I am sure that Katherine Powis, HSNY librarian, will be more than happy to help find you references that will be of aid your research. Katherine is usually in from Monday to Thursday and I am usually in the office every day of the week. To borrow books you must be an HSNY member and we can discuss that in greater detail when you visit.

Wednesday, January 23, 2008

Houseplants in Nebraska

I live in Nebraska and have house plants. Lately, after watering them we can smell mold coming from the pots. Is there something I can do about it, I don't want to throw them away.

If the soil in your houseplants containers is extremely stinky then you definitely want to take some action to right the situation since good potting soil and/or compost is usually quite odorless. Let me suggest a few things to try and hopefully you will not have to get rid of any of your houseplants.

A good thing to know right off the bat is that most houseplants require significantly less water in winter. Even though our homes are kept warm through the winter, the sunlight during the day is significantly less and our houseplants are simply not as active as they are during the summer months. Many houseplants we consider evergreen still go through a dormancy period in winter. With limited sunlight the plants are still photosynthesizing, converting sunlight into energy in the form of carbohydrates, and growing, but at a much slower rate. As a result, your plants water needs are not as great as they are during the summer when the plants are photosynthesizing and growing at a much faster rate. In winter I still try and water with some regularity but I definitely apply much less water. Each houseplant has different needs, but in general I am always advising people to water slightly less but with greater frequency instead of drowning your plants and waiting until they are bone dry to water them again. Even some plants, like succulents for example, I might water only once a month in the winter, compared to once or twice a week during the summer. Excess water that is applied to the soil and not taken up by the plant then sits and runs the risk of promoting rot of roots and soil in your containers. So, first of all, if you don’t already, consider watering with less volume in winter.

With that being said, let’s address your plants more specifically. Hopefully the plants are not that large because what I would recommend next is to carefully pull the plants from their containers and inspect the soil, roots, and containers. Create a work space for yourself because you may very well make a mess, and if possible do this during a cloudy day or at night so the roots do not run the risk of being burned by direct sunlight. What you want to find is soil that is not overly compacted or claylike. When slightly moist, a good potting soil you should be able to ball up in your hand and when you release it, it should fall apart pretty easily. What you do not want is soil that has broken down so much that it is either like clay or like pulverized dust. Next look at your roots. Healthy roots are usually white or light in color and firm, rotting roots are dark or black, squishy to the touch, and probably not very good smelling. If you have root rot take a sharp pair of pruners or scissors and get the rotten roots out of there; they’re of no help to the plant. Lastly, make sure your containers have adequate drainage holes in the bottom. All houseplants require containers with drainage holes, even if they are considered water loving plants.

I’m hoping that all you really have to do to right the situation is repot some of your houseplants. Spend the extra couple bucks on a name brand potting soil (Schultz, Miracle Gro, etc) because the soil structure will be better than generic bags of soil that inevitably seem to frustrate me. If your containers do not have drainage, switch them to containers that do. If you have succulents or plants that require maximum drainage, consider a layer of small stones or pebbles in the bottoms of your containers to create an additional buffer for excess water not used by the plant. Usually you want to repot in spring, but it sounds like the plants will benefit from being checked out as soon as you can find the time. Let me know how it goes and if you need further help. Good luck!

Tuesday, January 22, 2008

Jade Pruning in Indiana

I visited your site - - and was fascinated with the picture of the jade plant. I posted a picture of mine that we repotted this afternoon on my blog and linked to your site so that my readers could see what a beauty you are showcasing. Has this one been pruned a lot to achieve the shape? I am terrified of cutting on mine, even though it is really healthy, I'm thinking it could use some shaping. Are there any tips on how to prune, or do you just start cutting?

Your jade is gorgeous; thank you for sharing the picture and link to your blog.

As for that other fabulous photograph that was sent to me, the one on my blog that you referred to, I must be honest and say that I am not sure how much it has been pruned. It seems to me that that specimen receives enough light and therefore I guess that it has gone minimal pruning.

Most reference books on houseplants and succulents will tell you that jade (Crassula arborescens) do not require any pruning. As for your jade, I think it looks wonderful, but I understand if you would like to do a little pruning. One thing that you want to keep in mind which you already know is that jades are slow growing. In addition, because it is an older plant you want to prune as little as possible to achieve the look you are going for. The older a plant gets the more difficult it can be for the plant to recuperate after a heavy pruning. Pruning does redirect the flow of energy and carbohydrates within a plant to promote new growth, but with such a slow grower it may take a while before you see a lot of that new growth emerge. In general I might suggest waiting until this spring before beginning pruning your plant. Once the days are longer and there is more light in the sky the jade will be more active and resilient in the face of some pruning.

Regarding the cuts themselves, think about is the size of the cuts you will be making. Ideally you want to cut smaller stems and try to avoid making large exposed cuts so that the plant can callus those wounds as quickly and easily as possible. A few small cuts the plant will callus quickly and efficiently. Large cuts can take a longer time to callus, possibly allowing pests or diseases to penetrate the open wound. If you want to cut back some stems, cut them back to the lateral branch that they emerged from. You will most likely not get new growth from where you have cut, but new growth will emerge from the tip of the larger, remaining branch. If some branches have gotten long and leggy, you can cut them back a little, but be sure that there are some leaves remaining on the stem that can continue to photosynthesize. What you really want to avoid is leaving any large exposed stubs of branches that have no foliage. They will most likely just die back to the lateral branch that they emerged from, and again can be an entryway for pests and diseases.

It is very difficult to describe proper pruning cuts in writing, so if this is completely confusing, don’t hesitate to give me a ring in the office and we can chat about your jade in greater detail.

Friday, January 4, 2008

Growing Citrus Indoors in Rye, New York

I live in Rye, N.Y and I also have been having similar problems with many of my 2 dozen potted citrus. I have had most for 2-3 years and they have seemed healthy. Fought off citrus red mites last winter with horticultural oil and pre-treated them in September before bringing them into the house this year. They are in a sun room with ambient temps around 70 degrees. They get east and southeast sun for half of the day (when there has been sun). They are potted in 5 gallon pots with either a mix of citrus/cactus soil or Moisture-control potting soil mixed with orchid bark stuff. The pots have extra drainage holes and the plants are not allowed to sit in dishes with water.

They grew really well this summer with lots of flowers and fruit. The new leaves appeared chlorotic so I fed them as best I could with iron and minor elements as well as a general plant food (Ran out of the citrus foliar and citrus liquid I had brought from Florida several years ago.) They never really looked great, but.... I top-pruned them so they would fit in the house with the 2 dozen Rosa Sinensis I have and brought them in. I've since obtained citrus foliar feed (but can't spray while in the house) and some granular citrus food. I put about a teaspoon of this on them after bringing them in having read that citrus are "heavy feeders" and they looked kind of "pale".

They soon began dropping leaves which I assumed were the previous year's growth but the leaf drop continued and several plants began to get shriveled leaves which turned brown and the trees failed. No bugs, the soil smelled normal. I unpotted one of the "sick" plants (a Buddah's Hand) and found mostly roots, none circling the pot, no rotten roots or bugs in the soil. I cut away some of the larger roots and put the plant in a clean pot with the above mentioned soil mix and I'm waiting for something to happen.

So, basically I have had citrus trees with leaf drop of 1) Apparently healthy leaves; 2) Leaves that shrivel and brown around the edges before falling; 3) Branch tips that wilt and don't respond to watering (if previously dry).

Somehow I thought I had saved my "grove" last year after the mites, but I'm unable to fix their problems now. I'm attaching some pix with the hope that you can somehow advise me since what I read on your blog seemed entirely reasonable for Hibiscus and Citrus.

I would be eternally grateful if you could help me manage my indoor citrus.

Thank you for writing. I can’t even imagine how nerve-racking it must have been to deal with the red mites given the amount of citrus you have potted up. I’m so glad you were able to control the situation. Let me share with you my knowledge of citrus, along with the aid of some literature here in our library, and hopefully I can provide some new information to help you.

Regarding the sunlight it sounds like the room has a strong enough exposure that your many citrus get the hours of direct sun that they need. I assume in summer you place them in an area with an equal amount of direct sun.

A constant temperature of 70 through the winter sounds good. Your citrus could probably even tolerate colder temperatures, into the 60’s or upper 50’s, but I understand that you still want to enjoy your sun room as well. The only other thing about the temperature, as reiterated in my research, is that you want to make the temperature transition as smooth as possible when moving the plants indoors or out. I assume the sun room gets warm during the summer, but in the fall if the room stays around 70 then I would move the plants in while it is still nearest to that temperature outside. Of course we also need to take into consideration the nighttime temps in the fall and spring as they can drop pretty low compared to daytime temps. I have seen people leave their citrus outside until it gets in the 60’s or below and then move them into an enclosed, warmer 70 degree room and that can certainly lead to some shock and leaf drop.

Certainly the citrus and/or cactus soil is great because it has such excellent drainage. I would probably add some quality compost to it as well to increase the nutrient value and water holding capacity. I am curious to know more about how the plants in the moisture control and/or orchid bark mix are holding up. Both of those media can hold moisture for long periods of time without drying out and I was taught that all citrus enjoy being in soil that is allowed to dry out a little between watering. I’m sure the extra drainage holes you added make all the difference.

Citrus are heavy feeders, but you will want to concentrate more on when they are feeding most heavily. During the warmer months when the days are longest and the temperature and humidity is at optimal levels your citrus are going to be most active. In combination with the fact that they are all containerized, this means that fertilizing is most important through the spring and summer. Most citrus fertilizers have a higher first and third number, which means higher doses of nitrogen and potash compared to phosphorous. The nitrogen is important for the green of the plant, the development of foliage for photosynthesis. Potash is important on the cellular level because it aids the overall structural health of the plant. During the summer I would fertilize regularly every two weeks with a citrus fertilizer or another fertilizer as long as it is high in nitrogen and potash. If your local garden center does not carry a product specific enough I was able to find a number of adequate fertilizers for sale online. This time of year, since the plants are inside and still getting ample light, I might still fertilize but definitely less than during the summer. Since chlorotic foliage is an issue I might switch to a foliage fertilizer, with a high nitrogen content and lower phosphorous and potash, and apply lightly and sparingly through the winter. Usually I tell people not to fertilize in the winter at all but in your case it might help. Even though your citrus are evergreen they are still in more of a resting period this time of year. Over-fertilizing in the winter, when the plant is not active enough to take it all up, you can run the risk of adding too many soluble salts to the soil and that can inhibit nutrient uptake even if nutrients are present in the soil. I doubt you have, but if you fear you have over-fertilized, you do have the option of flushing the soil with a heavy watering and leaching out excess salts.

Aside from the fertilizing, the only other issue that seems most pressing that I haven’t mentioned is the humidity. Dry winter air is brutal on our indoor plants so increasing humidity in the room is the first thing that came to my mind when you mentioned shriveling leaves and wilting tips. I have oversized glazed or plastic saucers with gravel below all my indoor plants. Excess water that collects in the gravel “buffer zone” evaporates in the immediate area around the plant and should help those dry and wilting tips. Some times I will even put a little water solely in the saucer if I know the soil is moist enough. This winter I went a step further and finally bought a humidifier and all of my plants look so much better. Increased humidity will not only increase the health of the new growth and the older growth to hold on, but it will also help combat pests like the red mites who thrive in drier conditions. I think even a spray bottle with a fine mist would be a help during these dry months if that isn’t already part of your routine.

I hope this information helps give you some new insight and is not too repetitious to what you have already read or know yourself. If you have more questions send them my way or feel free to call me in the office during the work day to discuss. Good luck.