This is my second official season growing food and ornamentals in containers on a 130 sq/ft” deck. It’s a really nice outdoor space with a breathtaking, nearly unobstructed view of the Burrard Inlet, but it’s been tough learning the ins and outs of this little micro-climate, and has taken me the better part of 18 months of careful watching and experimental plating to begin having useful ideas about how to use the space.
A few things I have to contend with:
- No direct sun until the late afternoon, thanks to the upstairs neighbors’ deck and our western view. This means that light is thin in winter, and blasting in summer.
- No direct rainfall due to the above overhang. Plants not pushed up against the railing need hand-watering.
- Glass railing. This makes it very difficult for bugs to get to our plants, who have to navigate up and over the railing to pollinate. (Or infest.)
- Annual power washing. All containers must be moved from the deck every year for the building’s yearly cleaning, so they can’t be too big to move down a few steps to the parking lot or indoors. This means that 40-50lbs is about a heavy as a container, including plant, soil, and water, that we can manage.
- Unobstructed view means we are extremely exposed and get the brunt of most weather. In the heat of summer, the deck bakes in the afternoon sun. In winter, frost hits us first. The temperature difference between us and the street just on the other side of the building, is enormous. (Big enough to the point where I will often go out with a jacket on, make it up the driveway, and realize that I don’t need it!)
These are difficult challenges for any gardener to overcome, let alone an amateur like me. Here are some things I’ve learned so far, though.
Sturdy Roots Are Key
I’ve had much better luck bringing home steeply discounted plants from the nursery than I’ve had in trying to start seedlings. For some plants, especially fruit and vegetables of specific heirloom varieties, I obviously need to search out and purchase as seeds because who’s going to have a Tom Thumb tomato start for me to buy? Not anyone around here!
My lavender, shade grasses, and rosemary were all salvaged from the discount shelf at a local gardening center and are doing wonderfully. (OK, so the rosemary could be doing better, but it’s not dying.) My theory is that small root systems on new plants are too fragile for the intense moisture/heat fluctuations on the deck, and that even a half-dead plant with good roots stands a much better chance.
Glass is Deadly
Or at least, damaging. The glass acts as a bit of a greenhouse insulator, but our plants grow towards it as that’s where the sun is. In this way, the leaves will usually end up pressed right up against it, trapping heat and moisture in a way that wood or another porous material wouldn’t. Leaves that grow against the glass almost always wind up unhealthy, and eventually die. So while it’s been tempting to push my box containers right up against the glass railing to give them a better chance at soaking up rainwater, I’ve had to pull them all back a few inches to avoid the glass problem.
Don’t Depend on Pollinators
After 2 years, I’ve only just seen my first honeybee poking around the deck this week. Yes, it’s taken that long to make it onto the local hive’s circuit, and I will have to plant more wildflowers to make sure they keep coming back. Until now, though I’ve had to hand-pollinate a number of my plants, including the strawberries, but I try to buy self-pollinating varieties where I can, or plants that don’t need to be pollinated to be edible, like leafy greens. My dwarf lemon tree, which will apparently live happily in a 2-4 gallon pot, is self-pollinating, as well.
The afternoon sun we get is absolutely brutal, and combined with the lack of rainwater in spite of living in the Pacific Northwest, I’ve quickly learned that this means I need to throw away everything I thought I knew about gardening in a zone 8b temperate rainforest, and think in terms of drought-tolerance and heat mitigation, since those are the most pressing concerns during my growing season. Passive watering systems, like ollas or self-watering pots, are a necessity unless I want to be out there watering 3-4x a day in the summer. Unglazed terracotta and unlined wood is a no-go, and containers that have some kind of moisture barrier are a must.
You Can Compost Without Ground Access
Being both cheap and stubborn, everything I use on the deck gets recycled. This includes plant scraps, trimmings, and the soil itself. One of the big projects that I really wanted to see if I could tackle, though, was devising a completely earth-free composting system. I may have stumbled on one.
Bokashi seemed like a good place to start, but the bran is expensive, and didn’t like being stored in our highly exposed outdoor space. The $30 bag I’d purchased didn’t last long, but the nesting 5-gallon buckets I’d salvaged for the project were working, and half-full of half-rotted compost besides, so I continued to throw scraps in, including bamboo toothbrush handles and animal products, just to see what would happen if I left the bacteria to their own devices. I spent the better part of a year tossing the occasional organic scrap in, not turning it, not touching it, and covering tightly with a lid to see how the anaerobic process would do. (The lid went back on quickly – it stank pretty good.) In the meantime, I was treated to plenty of runoff from the bucket to use – nutrient-rich compost tea.
When the bucket was about 2/3s full, I let it sit for a while, untouched, tucked away in a shaded corner of the deck. Bokashi composting, for all its uses, still requires access to earth. At the end of the “pickling” stage, you’re to dig a hole someplace, dump the contents of your bucket, and cover with dirt for a time, after which it’s supposed to have turned into finished compost. So I thought, what if I just covered the compost with dirt (I used old potting soil) in the bucket, and left the lid off of it all winter?
Doing just that and checking again about 3 months later, the experiment was a success! All but the toughest bits of matter, like avocado pits and larger pieces of wood (the compostable heads of our dish scrubber, namely), all turned into fine, rich, finished compost.
In the future, I might get two buckets, since this process appears to take about a year, and I’d like to be able to alternate filling/finishing. I may also shell out for a bin that has a tap on the bottom, to make collecting the tea easier.
Composting isn’t the end-all be-all, though. Sometimes you have to get creative in other ways.
Be Prepared to Improvise
…or you’ll be spending a lot of money.
Container gardening isn’t cheap, unfortunately. There’s a lot more to it than just dumping seeds in a pot and watching them grow. Plants grown for food need a lot of water, a lot of nutrients, and a lot of sun. The Vegetable Gardener’s Container BIBLE says that an average summer squash plant needs more than a gallon of water every day, even under ideal growing conditions. In blazing afternoon heat, evaporation takes its toll quickly.
Large, sturdy plastic can be used to protect individual pots. I have a soft plastic washtub that I’ve encased in one such bag to create a greenhouse to grow ginger and start seeds. I have… problems starting seeds indoors, thanks to an overzealous cat that loves windows. Lots of seeds have been wasted this way.
For certain plants, such as my oak sapling, I’ve taken a page out of the book of traditional indigenous agriculture techniques, and buried a small fish below the root ball when repotting. (Small frozen fish like smelt seem to be a good size for containers, and each individual one costs pennies.)
More specific nutrient deficiencies can be managed (with time and practice), through natural means also. Coffee grounds and pine needles can be used to acidify soil, for instance, and contribute nitrogen. Burying rusty bits of scrap metal can help with iron deficiency. Unscented epsom salt can alleviate magnesium deficiency. (Learn how to properly apply salts to your plants here.) Blackstrap molasses has a whole buffet of micronutrients plants need, and it helps to feed beneficial soil bacteria too. And I’m sure we all know about egg shells already. Really, there’s not much of a reason to buy a dedicated fertilizer product unless you’re growing on a large scale or have plants that need a fast-acting nutrient to save them – and even then, noncommercial methods still work pretty well provided you’re willing to entertain alternative approaches to horticulture in general. Odds are though, your kitchen cabinets are already stocked with plant food! Even urine and pet waste can be put to use instead of tossed in the garbage or flushed down the toilet.
I experiment a lot in the garden now. I didn’t at first, because I was still getting very precious about all my plants, and I hated to see any of them die, even weeds. I had to get over this quickly, as space and nutrients are at a high premium in a container garden. A few weeds or even a single caterpillar can be the difference between success and failure for many plants.
But that small, compact scale can be a boon for horticultural tinkerers, too. If just maintaining a container garden isn’t exciting enough, playing with dwarf varieties, cuttings, and companion planting keeps things interesting on a day-by-day basis. Shuffling pots around to create super micro-climates – seeing which plants benefit being shaded by others, which ones fare better closer to the radiant heat of a wall, or more exposed on, say, some stairs, etc – is also a fun series of challenges. One of my favorite things to do is set aside a pot just for the purpose of capturing wild seeds, and paying attention to what winds up growing there, how long it lives, and what succeeds it after its life cycle ends. I wound up with a pot of beautiful wild stonecrop this way, which is something of an ornamental weed around here. It’s also how I get my moss, which I distribute around the garden as a kind of green “mulch”.
You can see what happens when you let plants go to seed, because the odds of them taking over your garden are slim. You can see how closely together you can plant certain species, or test yourself to grow something that isn’t usually thought of as a container crop, like garlic or squash. (Speaking of, my first batch of hard neck garlic should be ready in the next few weeks. I’m very excited, though I’d be lying if I said I couldn’t have given them more attention.)
For what few readers I have left, I’m sure you’re wondering why I’m not commenting yet on anything that’s going on. Honestly, I believe that most everything that needs to be said is being said elsewhere – that we are living in a crisis moment unprecedented in living memory, that the pandemic is a manifestation of nature’s hard limits on human activity, that there is a cowardly despot holding office of POTUS, that racism, homophobia, and transphobia are endemic to American culture, and that a riot is very much the language of the unheard.
If you’re browsing the internet and reading blogs in search of a balm for your guilt and existential worries, I don’t blame you. It’s not necessarily healthy, or right, but we all need a breather. I do hope that you’re getting out and getting your hands dirty as part of that process, though. Even when it comes to self-soothing, engaging our bodies is always a better strategy than trying to forget them. Take it from a chronic and lifelong dissociator: running away from your problems creates fewer solutions than you think.