CARE

TAKING CARE OF houseplants is not rocket science or anything remotely difficult. However, it does require a little insight. You might have to get into the rhythm of gardening indoors. But once you have mastered the art and science, the routine will become second nature. And the rewards will transform your home and life.

It is true that you shoulder more control (and responsibility) for houseplants than for their garden-grown counterparts. But that can work in your favor. When the weather fails to furnish rain for weeks at a time, it’s pretty much business as usual for your houseplants. You just get out the watering can. As with outdoors, indoor gardening is affected by Mother Nature’s antics. Paying attention to the environment is key when growing any plant. Proper watering, feeding, potting, and repotting can make the difference between success and failure. As for grooming, pruning, and all the other attendant aspects of gardening indoors, they might not be critical, but they will give you happier, healthier plants. Might as well go for the glitz, right?

POTTING AND CONTAINERS

Everything in this section is intertwined. That is the harmony of nature—you have to see the big picture. But the framework for successful indoor gardening starts when you fetch your new plant home and introduce it to the fleet. Without exception, I start by transplanting my new acquisition from its plastic container into a pot of my choosing. No chore about it; this is the fun part for me. I usually go with terra-cotta, but not always. I sometimes match the plant with a metal or faux container. But I always do something decorative. Beauty is what it’s all about.

Well, not totally. Aesthetics are important, but practicality is even more crucial. I think about the root system. I consider the plant’s future care. If it is a citrus, I am likely to give it a deep container because the roots tend to plunge down and I do not want to repot it again tomorrow. On the other hand, begonia roots are apt to grow outward, not down. So I give begonias wide, rather than tall, containers. When deciding on the size of the container, look at the roots. Have they filled the current container? If not, find a container of the same size. Sometimes I even demote the plant to a smaller footprint when the nursery has given it a huge pot to increase its perceived value.

In my houseplant-troubleshooting experience, I find that gardeners tend to overpot plants. Plants do get infinite root room in a garden bed, but that doesn’t translate to container gardening. As a rule, graduate a plant only one or two pot sizes at a time. When a plant is swimming in too much soil without sufficient roots to soak up the moisture, the soil conditions tend to get soggy, especially over the winter. It’s like giving a child shoes that are several sizes too big, hoping she’ll grow into them quickly. Her feet might eventually fill the space, but they’ll flop around while in the process. Same with plants. Whether you are potting a cutting or transplanting a plant, one step at a time is the way to go.

When you pot, be sure to firm the soil around the root system. Airholes will cause the roots to dry out. I am not suggesting that you cement the soil in, but make sure it fills all the gaps. I use my fingers to push it in (I have small hands). Another method is to use a pencil or stick to fill gaps. Then tap the container on the potting bench to settle it down, adding more soil if necessary.

It is critical to have space for watering between the soil surface and the container’s rim. For a large container, leave at least an inch between the soil and rim for this purpose. For smaller containers, half an inch should suffice. Without that lip, water will flow over the side of the container. Not only will it be a mopping mess, but the water will never have the opportunity to percolate down.

When purchasing containers, I think about practicality first and foremost. But I also take a long, hard look at the shape of a container before plunking down my money. Bean pot shapes (tapering to a smaller opening at their rim from a stout middle) are a bear when it’s time to repot. I use them only if there is scant chance the plant will ever need promotions. I never enlist improbable salvaged things with insufficient root room as containers because they are rarely suited for this repurpose. But I do use industrial metal cylinders for plants, and they make the job switch seamlessly. I spend a lot of time drilling holes for drainage. Many containers lack holes, but it’s simple enough to apply the cement drill. However, keep in mind that glazing might chip while you’re drilling. Don’t take the risk with anything expensive; that Ming vase would be better left empty.

A quick word about self-watering containers. I haven’t experimented sufficiently with these systems, but my gut reaction is to be suspicious. It seems unlikely that the soil will ever dry out enough to give the roots the oxygen they need, but I haven’t encountered a self-watering system that has lured me into giving it a try. And I enjoy watering my plants. It’s part of the experience.

SOIL MIXES

Finding the right potting soil also spells the difference between success and failure. It is paramount. When I first went to work in a commercial greenhouse, we concocted several custom potting soil mixes to suit the needs of specific plants. There was a fern mix, a begonia mix, a succulent mix, and so on. Nowadays, it’s more of a one-size-fits-all industry. And that seems to be effective. My advice is to explore several potting mixes and find the one that works for the majority of your plants. Sometimes, it’s not love at first sight.

I don’t attempt to make my own potting mix from scratch. I don’t have the time or facilities to sterilize loam or fiddle with a pile of ingredients. I rely on bagged, commercial potting soils. However, don’t assume that a mix will work just because it features a label declaring it a “Container Mix.” It’s wise to look twice at the soil you use for potting houseplants. Don’t assume all mixes are the same.

I use organic potting soils, but I don’t think any old organic mix is sufficient for my plants. It’s a mystery to me why soilless mixes have gathered such a following. Yes, they are lightweight, making your plants more portable and easier to ship. But do you carry your plants around continually? I move mine every once in a while, but it’s more important to heft a healthy plant into a prime position than tote around a poor anemic specimen.

I seek out a potting soil with soil and/or compost included. I feel strongly about this. Plants raised on a purely peat-based mix look like they’ve been fed a fast-food diet. I can tell the difference. I give my plants a good, strong foundation, and they respond with vigorous growth.

Beyond being organic, I also select soils that have a friable consistency. Many potting soils on the market have poor drainage. Fortunately, you can do a simple “squeeze test” to discover if the soil has the proper makeup. Grab a handful of lightly moistened soil, ball it gently into your palm, and let go. If it falls apart, it’s golden. If it remains in a glob, it will not drain well. Muddy soils can spell disaster for houseplants. The roots actually smother because of lack of oxygen, and it’s often a slow, painful death. I avoid mixes with vermiculite because it tends to give the soil a sticky, globby consistency. Although pearly white perlite is not particularly good-looking, I prefer it to vermiculite. But I often work with soils with no perlite or vermiculite.

Before potting with any soil, moisten it lightly (keep in mind there is a vast difference between moistened and soggy). Ideally, you should do so a few hours (or at least a few minutes) before potting to let the water seep in. Then stir up the soil to distribute the moisture. After potting, give the new transplant another drink. During the potting process, you’ve probably teased out and disturbed the roots, and they need water to settle in. After that initial watering, check for cavities where the soil has migrated down. If it has, top off with soil.

WATERING

All of gardening is interconnected. The way you water has everything to do with the type of soil you use. When I teach, my students always beg for a formula. “So, do you water every three days, or what?” they ask, pens poised. There are no formulas; there is no schedule. When I wake up in the morning, I stroll through the house visually checking my plants for dryness. All 300 of them. Some will be dry, others will not. If the weather has been cloudy and rainy, none will be thirsty. When it’s sunny outside, several will need a drink. Sometimes the whole crew has to be quenched.

How do you know when a plant needs water? Don’t wait for it to wilt. Withholding water until a plant slips into a faint is stressful, and stress makes a plant susceptible to insect infestations. Some people suggest “the weight test,” the theory being that dry soils are lighter than their wet counterparts. With several hundred plants, the last thing I want to do is pick up each one to determine whether the soil is moist or dry. Instead, I just eyeball it. It works for me, and it’ll work for you. Soil turns pale when it is dry, and that’s when it’s ready to be watered. Don’t let the soil get to the parched stage, even with succulents. If it becomes too dry, the soil will not take up water properly or distribute moisture evenly.

Of course, if you are new to this, start by doing the “finger test.” Insert your finger down an inch or so and feel the soil for dryness. With this method, you will gain a sense (literally) of what the soil looks like when it is dry. It’s a good way to get a feel for it.

As for top dressing, I occasionally use sheet moss or river stones and sometimes even go the pinecone route. It adds another dimension to the look. But a top dressing can add to the guesswork when watering. The only wise counsel I can share is to wait until you have a feeling for how often a plant dries out before hiding the soil under top dressing. Or be prepared to dig a finger in periodically to sample the soil.

Depending on the weather, plants tend to need more water in the summer than in the winter. But during a summer rainy spell, you might not need to water at all for a week or more. And when the temperatures outdoors are frigid and the heat is running full blast both day and night, you might need to water daily. But, in general, plants dry out more frequently during the warmer and sunnier seasons of the year.

How much water should you deliver per serving? If you have potted your plant correctly, you will have space between the soil surface and the rim edge. Fill it up with water, then let it slowly seep down. There is no need to fill it several times at the same serving. When a plant is watered regularly, the water should penetrate slowly down to the roots and nourish them. If the water you have just served goes rushing down and out the drainage hole like a waterfall, something is wrong. When soils are too dry, they fail to moisten like a sponge. Instead, they just shed water—it’s like storm-water runoff. The remedy is to soak the plant from the bottom by adding water to the saucer and letting it draw up gradually. After you’ve remedied the emergency, go back to watering normally, and apply water more faithfully in the future.

Saucers are imperative for keeping your furniture and floors tidy. I select handsome ones because it’s all about aesthetics for me. Cheap, clear plastic saucers aren’t my speed. But there’s nothing wrong with enlisting your plates or using copper trays. I don’t own any expensive furniture, but I still don’t want to mar the surfaces in my decor. Keep in mind that unglazed saucers can leave mildew marks on wood. It might be wise to add a cork trivet or tuck a tablecloth underneath a plant.

The main trick is to find a saucer that is wide enough to handle any overflow that might dribble out of the drainage hole. Even if you water a plant properly, there is bound to be a little excess that puddles out. You need something capable of catching that runoff effectively. Because I’m caring for hundreds of plants, I do not empty each saucer after the water dribbles down. Everything does just fine nonetheless.

I have hard, mineral-rich water in my home. With this quantity of plants, I certainly don’t purchase bottled water for them. And it isn’t an issue. I’ve lived in towns with treated water, and the plants drank without problems. If you find your plants are suffering and suspect your water might be the culprit, try collecting rainwater or purchasing the bottled version.

I use a watering can to water and aim the spout strategically at the soil surface. I can’t imagine watering a small potted plant with a “rose” sprinkling attachment on a watering can. Although African violets are notorious for their dislike of water sprinkled on their foliage, they are not alone. In cloudy weather, especially in winter, make sure not to wet the leaves. My containers come in all shapes and sizes, varying from tiny on up, so I use a slender-spouted can that I can point precisely. It makes all the difference.

I water in the morning to let the plants drink all day long. It’s a ritual, really. After watering, that wonderful smell of earth and moisture wafts into the air. My complexion loves it. It smells like home.

FEEDING

I think gardeners put too much emphasis on the need to feed houseplants, but I don’t grow in a soilless mix. My soil mixes have built-in nutrition, and the plants need not survive only from one meal to the next. Fertilizer isn’t a life-or-death situation. When I worked in a retail nursery, we always told customers to feed with a balanced fertilizer with an even distribution of nitrogen, phosphorous, and potassium (N-P-K), such as 20-20-20, once every three weeks or so. Rather than a chemical fertilizer, I now use an organic fish emulsion at the same intervals—once every three weeks. Although it is not a balanced fertilizer, it works when combined with good potting soil underfoot.

One piece of advice remains the same. Do not fertilize during late autumn and winter, when light levels are low. There are exceptions. I’m always monitoring for houseplants with that lean and hungry look. And I find that gardenias, citrus, and stephanotis need a shot of fertilizer in February as soon as light levels begin to increase. If any plant begins to look starved, I serve up appetizers. It’s the same old sensitivity refrain I’ve been harping on throughout this section. When you start fertilizing in spring, do it gradually, diluting the fertilizer a little more than the label directions suggest. Otherwise, faithfully follow the instructions. From a plant’s point of view, more is not better, and gluttony can lead to problems down the road far more serious than mere obesity.

PRUNING

Not everyone loves to prune, but I do. My mother-in-law used to rant, “How would you feel if someone cut off all your fingers and toes?” after I went on a pruning spree. But when the begonias (or whatever) bristled with new growth, she beamed. I like to keep a tight ship. And I think pruning brings about a sharper picture in the long run.

I’m almost always brandishing pruning shears. Although the rampage against leggy limbs reaches its high point in spring, I hit shaggy appendages whenever they appear. In winter, plants often make stretchy growth because of diminished light. Away it goes. In autumn, when plants re-enter the house after their summer sojourn, they often become too large for their allotted space. Clip. And sometimes I just want to exercise control and encourage a plant to branch out during the summer or sprout fresh from the base in winter. Off with its head. I think good grooming spells the difference between an okay crowd of amateurs and a turned-out kick line of well-rehearsed performers.

When pruning plants, make your cut right above where the leaf blade juts out, and be sure there is a side sprout waiting in the wings to branch out. Some plants, like begonias and pelargoniums, have what we call “blind eyes” with no side shoots. They might sprout lower down or push another branch up from the base, but they will not branch just below the cut.

If pruning has you quaking in your boots, I can only say that I have never (or almost never) murdered a plant by pruning. I have ended up with some gawky specimens as a result of clueless cuts, but time healed the wounds. And I sometimes chopped too enthusiastically in winter and sent the plant into a temporary tailspin. But if you play it safe and prune in spring and make sure there are side sprouts, you are on fairly safe ground. Your plants will have more branches and increased bloom, and will form a handsomer picture. Why would you resist?

GROOMING

When watering my plants, I come back to the faucet via the composting can clutching a handful of dead leaves and flowers to discard. Forever in the process of growth, plants are also continually shedding. But it’s no worse than your cat. And most of the time, the cleanup is considerably less arduous.

I figure that a yellow leaf will probably never look prime again. I’m not talking about slightly pale green leaves, which can darken up if given fertilizer. But when a leaf is going south, what is the point in leaving it to tarnish the plant’s image? Might as well clip it off. There is no hope for a brown leaf. It’s gone. Same with spent flowers and flower stems. Take them away before they attract disease spores. The scene will look so much better.

Some plants make more of a mess than others. I adopted Loropetalum chinense this year, and I am beginning to regret it. Each flower is composed of many thread-like pink petals that look lovely while they are prime. But when their moment of glory passes, they shower all over the floor. Or, even worse, they shrivel up and cling to the branch like the Wicked Witch of the West’s broom. You know the look. Same for the powder puff shrub, calliandra. It is divine while blossoming in autumn, but what a mess after the show is over.

Of course, shattered petals are not always an eyesore. I sort of like the way a camellia’s petals float to the floor. Ditto for fuchsia blossoms. And not all plants are self-cleaning. For example, you have to snip off pelargonium flowers. But keep tabs on it. Basically, if it looks ugly, get rid of it. This is your home, after all. You make the rules.

INSECTS

Whenever I lecture or teach, the first question I hear from people on the verge of adopting houseplants has to do with insects. Are they a problem? Not in my house. That’s the truth. I don’t grow plants that are prone to insects. I keep my home temperatures cool, which really helps for limiting insect issues. I check the plants carefully for bugs before incorporating them into my home garden. I wish I had room to segregate them, but I don’t, so I monitor them carefully. If a problem occurs with a plant, I usually just discard it. That’s the way I deal with bugs.

My approach to pest control is to treat my plants very well. When a plant is healthy, insects rarely infect it. Watering regularly is key. If a plant is invaded by aphids (and that is generally the full extent of my issues), it is because I’ve somehow neglected it. Beyond watering, light levels also affect a plant’s overall health. When a plant isn’t getting sufficient light, it will suffer. I grow plants only where they have a good chance of thriving.

I grow organically in my home, so I don’t spray. On the very rare occasions when I really, really want to keep a plant despite a problem, I start with very mild organic insecticides, such as insecticidal soap or neem oil. Ultra-fine horticultural oil is another option for most houseplants. If these remedies don’t work, I discard the plant. Keep in mind that organic sprays must come in contact with the insect to be effective.

No matter what I am applying, I always spray outdoors and wear protective clothing. For all insecticides, even the organic formulas, always read, understand, and follow the manufacturer’s recommendations and warnings. If a spray is not prescribed for a certain insect, do not apply it. My agricultural-extension agent warned that insecticidal soaps sometimes do not work with hard water. In addition, certain plants might be sensitive to soaps and oils. Ferns—especially maidenhair ferns (adiantums)—and some succulents (I have heard that crassulas are sensitive) can react negatively. And be careful when you bring a plant back into the fold after applying any sort of treatment. Keep it away from pets and kids.

Watch out for insects. Needless to say, it is much easier to get a grip on a bug problem when it is fairly contained. When pest population numbers multiply, the nightmares begin. Your best method of patrol is to learn to identify the usual suspects. For the most part, houseplants tend to be pestered by aphids (clearly visible with the naked eye, they look like green, cream, or black many-legged critters about the size of a tiny water drop, usually found on the young leaves and flowers), spider mites (visible if you have great eyesight, these web-forming red bugs crawl on the undersides of leaves), mealy bugs (easily visible cottony masses often wedged in the juncture between leaf and stem), root mealy bugs (cottony masses in the root system and a pill to combat—just toss the plant), whiteflies (tiny but visible white flying insects that roost on leaf undersides and take wing when you disturb the leaf), and scale (easily visible little brown raised bumps on the leaf or stem surface). I occasionally get infestations of fungus gnats, especially when I am raising seedlings and watering them frequently (they dote on constantly moist soil surfaces). They are unsightly little flying bugs, but they don’t bother me and I don’t worry about them. Although some indoor growers have issues with slugs, they aren’t one of my problems. Slug baits are available, but a simple diabolical beer trap of your favorite lager poured on a pie plate should do the trick.

Purchasing a hand lens or magnifier is a great idea when working with plants of any kind. Not all bumps and deposits on leaf surfaces are bugs. Some plants, like gardenias and passion flowers, have an exudate that forms on the leaf surface. It does no harm.

If you do opt to spray a plant for an insect problem, keep in mind that one spraying is probably not going to squelch the problem, especially when you are working with an organic method. After you identify the perpetrator, learn about the duration of its reproductive cycle and remember to keep up a regular regimen. Or try predatory insects, which work to keep a population in check. (But if your predator eats all of its prey, it will starve, so you will need a resupply.) I have not had to work with predators. I have a resident population of ladybugs that does a lot of patrolling. Unfortunately, Einstein has a vendetta against ladybugs, but he hasn’t succeeded in decimating the population. Yet.

Needless to say, if you see a problem, immediately segregate the imperiled plant and its livestock. If at all possible, put it outside, away from the rest of the indoor-plant community. But don’t assume that Mother Nature is going to step in and sort things out. When insects find a promising meal ticket, they tend to hang around the café and chow down. Intervene. Outdoor pests are rarely an issue when you put plants outside, except for slugs and snails can be a problem. Monitor for and remove them, especially when you bring a plant back inside.

DISEASES

Keeping a plant tidy and its foliage dry will go a long way toward limiting your disease issues. Again, a healthy, well-fed, unstressed plant should not have problems. But if you find a leaf that is mushy or has brown spots or browning edges, get rid of the offender. Don’t wait for whatever has gone wrong with that leaf to infect the rest of the plant or its neighbors. Just take it away.

I very rarely have problems with diseases on plants. I steer away from sticky wickets. For example, I don’t grow heliotrope in the winter because it tends to have issues: I can’t provide sufficient sun for a heliotrope to thrive, so it is continually stressed. I have tried to recommend plants that are a good match for the average home. Nobody wants to watch a plant pout until it perishes. In that same spirit, I avoid certain plants because they have a tendency to develop powdery mildew. Mildew is my foremost bugaboo indoors. Although I have excellent air circulation in my house (old buildings tend to be drafty), the breezes are not sufficient to keep rex begonias from getting powdery mildew. I just avoid growing them. And again, always segregate a problem immediately. By all means, make that call to the extension agency to get a diagnosis for your problem. But in the meantime, put distance between the sick plant and the rest of your pack.

TROUBLESHOOTING

All these elements combine into one big care picture. Often, indoor gardeners panic and only make the situation worse. A better method might be to hold the status quo. If a plant is beginning to falter, drenching it with water is not going to remedy the problem. Ditto for throwing on the fertilizer when a plant is on its deathbed. Instead, keep up the slow-but-steady watering regimen that houseplants prefer and don’t try to serve a feast to a plant when it’s headed for the hospital. If your plant is on shaky ground, check out the root system. The roots should be healthy and slightly swollen, rather than shriveled or nonexistent. If the roots do not warrant more room, don’t assume it needs a pot graduation. If the root system is insufficient, a wiser plan of action might be to demote the plant to a smaller container.

Moderation in all things isn’t a bad approach to indoor gardening. Rather than reacting, think through the problem—and its remedy. Look for the source of the issue. Is the plant growing in soil that has good drainage? Are you watering properly? Does the plant have sufficient light? Make a mental check list and do the detective work. Keep your finger on the pulse of your houseplants. The relationship will blossom.

FINALE

So that is what it’s like in my home. This is my life. Yes, I had to juggle the plants around a little so you could see the forest for the trees when we were photographing. But the plants in these pages reside by my side day in and day out, season after season, throughout the years. And I’ve got to say that we’ve grown accustomed to each other, like family. The ctenanthe is used to getting whopped as I breeze by on the way into the kitchen, and the sedum that showers from its container has learned to take some gentle stomping as I move around the house.

The point is, we’re intimate. I can’t imagine an existence devoid of the plants that fill my life and living space. I couldn’t survive in a world without green. And I’m not so very different from you. I’m hoping you will find it contagious. No, you don’t have to do this with my level of fervor or fanaticism. But bring a few plants into your home and it will make all the difference. It will change your world, I promise.

VỆ SINH

Khi tưới cây, tôi loại bỏ những cụm hoa và lá già, đã héo. Trong quá trình sinh trưởng, cây cối cũng liên tục rụng lá. Nhưng không tệ hơn mèo. Và đa phần thời gian, việc vệ sinh cây trồng ít vất vả hơn nhiều.

Tôi nghĩ rằng một chiếc lá vàng sẽ không bao giờ trông hoàn hảo được như trước nữa. Tôi không nói đến những chiếc lá xanh hơi nhạt, có thể sẫm lại nếu được bón phân. Nhưng khi một chiếc lá hướng về phía nam, việc để nó làm hoen ố hình ảnh của cây thì có ích gì? Hãy cắt bỏ nó đi. Không còn hy vọng gì đối với một chiếc lá đã nâu đâu. Hãy để nó biến mất. Tương tự với hoa đã tàn và thân hoa. Hãy mang chúng đi trước khi chúng thu hút các mầm bệnh. Chúng trông sẽ đẹp hơn rất nhiều.