growing upside-down tomatoes on the roof
Spring is here, and many of us are wistfully dreaming of growing and eating
our own vegetables. Unfortunately, a lot of us don't have the room to
grow plants in a "traditional" garden setting.
In recent years upside-down vegetable planters have become extremely
popular. Vegetables can be grown anywhere that a hook is available —
on a balcony, a flat roof, or even suspended over a vegetable garden
where low-growing crops like squash are planted below. Rodents and
ground-dwelling insect pests can't reach your veggies, and the plants
don't need any staking.
Unfortunately, commercial versions of these planters can turn your
finances upside-down too, with some selling for as much as $50 each!
There are less expensive versions, but they lack flexibility, and in
many cases, quality.
With a little bit of time and some readily available materials you
can build your own planter that will grow herbs (on top) and tomatoes
(on the bottom) for only $5-6 or so per planter. The containers are
rugged and reuseable, so an investment now could last years.
Our yard is heavily shaded — the previous owner had a cabin in
Minnesota and came back with a sapling spruce, arborvitae, or fir for
his Illinois backyard every time that he returned from a trip. Over the
course of 30 years he amassed quite a lot of trees, so the only sunny
spot happened to be on the flat roof over our garage. And so began our
foray into the world of upside-down gardening in 2006...
- one 5 gallon bucket, preferably in a dark color to prevent UV damage
- one lid for 5 gallon bucket
- one small piece of landscape fabric, cloth, or an old nylon
- two small straight sticks, bamboo plant supports, or metal rods, not exceeding 8"
- one tomato plant
- five gallons of soil mix
- one drill with bits
- one 2⅛" hole saw, jigsaw, or keyhole saw
- one spool 16 gauge wire (for ¼" drill bit) or length of 2⅜" rope (for ½" drill bit)
- spraypaint (optional)
- something to hook your tomato on, about 6-8' above ground
In our experience, not all tomato varieties perform equally well when
grown in upside-down planters. Larger beefsteak varieties like 'Big
Boy' or heirlooms like 'Brandywine' don't produce enough fruit and often
get blossom end rot. Smaller varieties like cherry and olive tomatoes,
'Fourth of July', 'Early Girl', and yellow pears seem to perform much more
reliably. We've also had excellent success with Sweet Million, Sunsugar,
and Juliet.
This doesn't mean that you shouldn't try a roma or your favorite heirloom. Just be prepared and take steps to prevent blossom end rot by keeping your soil moist and making sure that there's enough calcium in the soil.
The first step to creating your own hanging tomato planter is to obtain
a five-gallon bucket and lid from somewhere. Most hardware stores
sell them for about $2.50 per bucket and another $1.00 per lid. I
bought mine from a store that supposedly let me 'Save Big Money.'
Flip the bucket upside-down and attach your
2⅛"
hole saw to your drill.
This is the same size as the hole saws used to cut holes for doorknobs
in doors, so it's fairly common. It also happens to be the exact same
size as the inner lip of my bucket.

If you don't have a hole saw, that's OK. A jigsaw, keyhole saw, or
even a serrated kitchen knife might do the trick. Regardless of what
method you use, be careful — no amount of tomatoes is worth the
loss of a finger!

Drill or cut a
2⅛"
hole in the bottom center of the bucket, then
flip it over so that the bucket is upright again. Swap out your holesaw bit
(if you used one) with either a ¼" or ½" drill bit, depending on
how you plan to hang your tomatoes. If you're using wire, you'll use
a ¼" bit. If you use rope you'll want a ½" bit.

Locate the spots where the handle meets the bucket and drill your
hole halfway between that point and the top rim on both sides (see
the picture if this is unclear). Drill two more holes in the other
sides of the bucket until you have four of them, evenly spaced, with
two under the handle.



The first time that we grew upside-down tomatoes they ended up looking
a little out-of-sorts in our neighborhood, especially when the buckets
weren't all the same color. The next year I bought a can of $5 terra
cotta spray paint and painted the outside of the buckets to look
more like flowerpots. Now things looks much nicer and people don't
expect to see Jed and Daisy May Clampett sipping moonshine nearby.
If you'd like to paint your buckets, hang them in a well-ventilated
place (outdoors, from a tree, works well) and spray the visible outside
surfaces with your paint. Don't spray the inside, though!


We discovered that tomato plants placed inside those little holes had a
tendency to fall out before the roots developed, so it's important to
use landscape fabric to help keep the plant in place. Cut a square
of landscape fabric, cheesecloth, old nylons, or some other drainage-friendly
thin fabric on the bottom
of your bucket. Then cut two small sticks (we use bamboo plant supports)
to and make an 'x' like we show in the photo.

The sticks should be smaller than the width of the bucket, although the
landscape fabric can be larger. These will eventually go inside the bucket.

Fold your patch of landscape fabric into quarters, then locate the
inside corner. Cut a small slit into it as shown.

When unfolded, there should be an 'x' in the center of the fabric.

Lay your bucket down on its side, take the tomato out of its pot, and
push the rootball through the hole so the tomato is hanging out of the
bucket and the roots are inside. Leave the bucket laying sidewise
until the next step.


Now we're getting into the tricky part! Since you need to be able to work on
your tomato's root ball without damaging the plant, you'll need to find two
supports of equal height that you can set your bucket on. We usually use
two upside-down buckets, but the corner of a low railing, two cinder blocks,
two chairs side-by-side, etc. all work equally well.
Position your supports wide enough apart so that your tomato can hang down
between them, but close enough together so that the rim of the bucket can
provide support.


Now look inside your bucket and slip root ball through the 'x' in the
center of your landscape fabric. This will keep all of the dirt from
washing out of your bucket.

Next, push the two sticks through the root ball (anywhere in the middle
of the rootball) to create an 'x'. This will hold the root ball in place
when the bucket is filled with soil.



Put some of your soil mix in the bucket until the root ball is covered,
then grab the 'x' formed by the sticks and pull your tomato up a couple
of inches. The idea is to pull the root ball further into the bucket
so that it's not right at the edge. You want to pull it in about four
inches or so unless your tomato is too small — use your judgement.

Finish filling the bucket with soil. We've found that Miracle-Gro
soil mixes work quite well, but we usually mix our own soil with
excellent results. Make sure that you pack that soil in well (but
not too hard) — you don't want it compressing too much later.

Whether or not you're now done depends on how early you're planting your
tomatoes. We like to plant them 3-4 weeks early, put lids on the buckets,
and grow the plants right-side-up during that time period.
We set the buckets out in the sun and either cover them with
cut-off milk gallons or glass jars or bring them into the garage if
the nights are going to be cold.
This allows the roots to grow downward through the bucket (which will
later become the top) so they won't dry out as much. It also gives
your tomatoes a head start.
If you decided to take this route, snap a lid on it, flip it over, and grow the plant
upright until warmer weather hits. Come back to this point in the
tutorial and you'll be able to pick up where you left off.
This step makes the true value of the five-gallon tomato planter apparent. It
seems silly to have all of that wasted soil in the planter, so why not plant
something else on top? If you took your bucket off of the supports in
step #7, put it back on there. Take the lid off if you had it on and
scoop out any excess soil until you're about two inches or so below the
rim.
Prop up the bucket on supports so that the tomatoes aren't squished and
tie your supporting wire or rope through the holes that you drilled
earlier. The type of knot used doesn't really matter as long as it's
solid. The only other really important thing is that the length of cord
or wire between the holes is the same length -- otherwise your bucket will
be crooked.
It's possible to hang your tomatoes from their handles, but over time
the buckets warp or breakdown in sunlight and we had several handles
pop out. There are few things as disheartening as finding your tomato
plant and its crop crushed under the weight of five gallons of wet soil.
Now we don't take any chances and hang them with wires instead.
Finally, plant your favorite herbs or peppers on the top! We've found
that three pepper plants fit in the top of a bucket quite nicely,
and we've grown them all -- banana, bell, cayenne, and sweet red --
with great success. Parsley and basil do phenomenally, but cilantro
and dill do not (they seem to 'melt').


Hang your tomatoes from a hook (or a rail with an 'S' hook) and you're
ready! We have a sunny, flat rooftop over our garage, and during
the first few years I used a stand built out of iron pipe to support
our tomatoes. Unfortunately, it wasn't very stable and the whole thing
collapsed during a freak windstorm. A new, sturdier one was built out
of wood instead.

It's important that your tomatoes stay moist (but not sodden!), so water
them every day. We set up drip irrigation on ours with a timer, although
a small submersible pump in a rain barrel would probably work just as
well.
These tomatoes were planted in mid-April, grown upright for three weeks,
then hung in May. The photos were taken in late June.

As you can see, the garden is alive in well in 2013. The new support
for the tomatoes is working well, and we plant up to 18 tomatoes and
50 peppers in the upside-down planters.


