Garden theme - Outer Space

My daughter said that she would sometime like to have a topiary tree clipped to look like a rocket on a launchpad. I think there is a skinny juniper called 'Skyrocket' but probably it wouldn't have enough foliage around the base to make proper fins, so if she wants a realistic looking rocket topiary she might have to make a wire frame.

We thought there would need to be some other space-theme elements in the garden so the rocket wouldn't look out of place, and we amused ourselves furnishing an imaginary Space Garden.

It needs a flying saucer - this could be a metallic birdbath or fountain on a slender pedestal, with a ring of LED lights around the rim.

The flying saucer needs surroundings that suggest alien worlds. What about a ground cover of black mondo grass with Allium cristophii (ornamental onion) floating star-studded globes above the black plain? Or a gravel garden planted with 'Living stones' (lithops)?
And cactuses - they often look like aliens. Elephant's Foot also looks suitably intergalactic.



(Photo shows an alien family slightly bemused by the Earth garden they are visiting.)
















Ornaments are practically mandatory. Anything is possible, from an orrery to a garden gnome in a space suit. An Aeolian harp to play the music of the spheres... A fountain with a ringed planet made of glass spinning on a swirl of water...

What plants could we include? Sunflowers, of course... maybe decorated with stick-on eyes, ears and antennae so they look like extra-solar tourists. Moonflower vine. Star jasmine. Lunaria, for its moon-shaped pods. Cosmos. Aster. Rocket. Jupiter's beard. We would love to include Venus's fly trap, not only because of its name but also because it looks so spacy, but it wouldn't survive in the open garden. Maybe the garden can feature a special habitat, an interplanetary Wardian case, to accommodate Venusian visitors.

It was fun to play with a few ideas for a space-themed garden. If anyone has actually made one, or would like to add to the lists of plants or ornaments, the Impatient Beginner would like to hear from you.

Daffodils and Gazania ground cover

Well, we didn't win Tattslotto so it looks as if we will have to do without our two-storey garage/greenhouse.

In any case, there will be changes in the garden. The big windstorm reminded me of the danger of the gum tree near the house. The tree will have to be removed - with regret, because the birds and possums will miss it.

In the space vacated by the gum tree I intend to plant two or three wattles of a sort that do not grow tall ... Acacia podalyrifolia if I can get it in Tasmania. I love its round silvery leaves.

While digging an extension to the bulb garden I discovered an old concrete footpath buried under a layer of three inches of topsoil. No wonder the grass never grew well there! I'm not up to the job of removing the concrete (as the previous owners weren't) and more topsoil is not an option, so I am thinking of other choices. I would prefer a ground cover plant so I want to try Gazania rigens var. leucolaena over the buried concrete.

This gazania is tough and drought tolerant. I hope it will be able to cover that difficult spot where grass can't grow. If it is successful, then I will extend the area that it covers into the bulb garden. In time it can form a silvery carpet out of which the naturalised daffodils, narcissus, freesia, white nerine and zephyranthes appear in their season.

I bought a bag of twenty daffodil bulbs to start the new extension to the bulb garden. They are simply described as "yellow" so I expect they are the typical golden-trumpeted daffodil. Today I will finish digging the ground, plant the daffs and add some cuttings of the silver leafed gazania. I'm looking forward to spring.

Wish list - Greenhouse on top of Garage

We have an old fibro-cement garage. The walls are cracked, the roof is a rusted ruin, the floor is uneven. It needs to be replaced and my husband has been looking at prepack steel sheds to see whether one of them be a suitable replacement.

I would love to have a greenhouse, especially one with electricity and water connected. If I had a greenhouse you would always know where to find me! Alas, our suburban block is too small to have both a greenhouse and a garage. Dear Husband is correct in saying we need a garage, and it makes sense to build a slightly bigger garage than the existing one so he will have space for his woodworking tools. It makes sense, all right... but I wish...

I had a flash of inspiration. Could we put a greenhouse on top of the garage? Have a two-storey combined garage/workshop/greenhouse? I loved the idea immediately. Imagine it - a possum-proof vegetable garden - a warm sheltered spot for the hydroponic tomatoes and cannas - electricity for the hydroponic pumps - a safe pond space for Katherine's fish. In my imagination I have already begun to design it. The staircase annexe can incorporate a water tank to store rain runoff from the roof. There can be solar panels along the north-facing knee wall.

Obviously such a building would cost considerably more than a simple steel shed. There's the rub. Our pension income is limited (particularly worrying now that financial institutions seem a bit tottery) so we won't be able to afford it unless we win Lotto. I am on my way to buy a ticket now!

Tropicanna in black urn

Part of my hydroculture experiments, the canna is growing in scoria medium. It is growing well, though it seems to be smaller than similar types that I have seen growing in soil. However, they may simply be older plants.

Next year I think I will add some of those mahogany coloured nasturtiums. They should do well in the same conditions as the canna and the colours will complement each other.

Originally I had intended to paint the urn with very fine marbled veins in olive, charcoal and light coral - similar colours to those in the canna leaves. Now I think it looks better simply in black.





Here is a close up of the canna's beautiful leaves.

Rough plan for small pot-in-pot planter made from plastic milk bottle

Use post-consumer plastic bottles for this project! We get milk in 3 litre bottles with handles as in the attached sketch and I think 3 litres will be a suitable size for a basic stacking unit of the "strawberry tower".

Cut an access hole near the top of the milk bottle. This hole must be big enough for a small plant pot to be put inside the milk bottle. Cut a drainage hole near the bottom of the bottle, about 2 cm above the bottom.

The water reservoir will hold about 500 ml. A tube made of synthetic fabric (spunbonded polypropelene or polyester - think geotextile, agricultural fleece, or nonfusible nonwoven interfacing) will connect the water reservoir to the plant pot. Right now I am thinking I will make a tube of synthetic fabric about 5 to 7 cm high and 2 cm in diameter and fill it with sand to act as a capillary tube to wick water up to the plant but I have not tested this yet.

A "floor" is needed to separate the water reservoir from the upper chamber of the bottle. Cut a margarine container down to about 2.5 cm in height, cut several drainage holes (about 1 to 2 cm in diameter) in its bottom and invert it --bottoms up!-- in the base of the milk bottle. The margarine container will not fit perfectly but it should be large enough to hold the actual "floor". Cut the "floor" to fit the milk bottle cross section. Use a disposable plastic plate or similar material to make the "floor". Remember drainage holes. We are trying to make a "floor" sufficiently strong and stable to support the sand/coir and the plant in its pot. Do not insert the "floor" in its final position just yet.

The capillary tube will have to pass through the "floor". Cut a 2 cm hole near the centre of the "floor" and thread the tube through the hole so the "floor" is at the approximate mid-point of the tube's length. Now the "floor" can be put in position on the margarine tub. The capillary tube should reach to the bottom of the water reservoir.

Now put about a 2 or 2.5 cm layer of the sand / coir mix on top of the "floor". The capillary tube should not be buried. Make sure that the end of the tube extends out of the sand mix distinctly. The plant pot will have to be centred on the tube, and good contact will have to be made between the tube and the potting soil in the plant pot.

Now take the plant pot that will be put inside the milk bottle chamber. Cut several 1 cm drainage holes in its base, and in the centre of the base cut one 2 cm diameter hole (or whatever diameter the capillary tube ended up as). Insert the plant pot into the milk bottle and make sure that the capillary tube reaches through into the plant pot. Fill the pot with potting mix and plant the seedling and water in.


Use the overflow hole to fill the water reservoir. Occasionally it may be necessary to add water from the top - because constant bottom-watering may cause salts to build up on the surface of the potting mix - but generally watering will be done via the water reservoir. Evaporative loss should be fairly small. It would be interesting to see whether the relative humidity inside the shell formed by the milk bottle is very different from the humidity outside, but I don't have a good way to quantify it. The test of this growing system will simply be whether the plants thrive, and I hope they will.

Now for something completely different. I expect my new flush cutters to arrive tomorrow so I am likely to get obsessed with wire work for a while. This is probably the last post on Gardening for at least two or three weeks.

Musing on the under-pot zone

Have you noticed how potted plants try hard to get their roots out of the container? Potted pelargoniums, marguerite daisies and cordylines dawdle along until they get their roots into the soil underneath the pot and then they put on a spectacular flourish.

What causes this? It can't simply be that their blueprints tell them to grow their roots to a certain defined extent, because roots try to escape from very large pots as well as small ones. They must be looking for greener pastures. Perhaps the soil under the pot is cooler and moister than that inside the pot, or perhaps there are better combinations of water and air in the under-pot zone.

I am thinking about this in designing the strawberry towers mentioned in an earlier post. I would like the plants to be as happy as possible in their hanging containers while at the same time I would like them to be low maintenance and only require watering and turning every two or three days.

So I am thinking about ways to simulate the under-pot conditions that plants seem to like and ways to create these conditions in the hanging containers. My earlier designs for the hanging containers included a water reservoir (like the pop bottle planters or a self-watering pot) but now I am inclined to try a base that is filled with coarse sand (like a miniature capillary watering tray) with a top unit containing potting mix set on top of the sand. Plant roots should be encouraged to spread from the top unit into the sand-filled base.

Experiments are needed to establish whether plant growth would be better in this type of system than in the simple water well pots, and to establish whether plants would prefer the top unit to be set into the sand or suspended slightly above it, and whether sub-irrigation or top watering would be best, and whether fertiliser pellets would be better placed in the top unit or in the sand... There are lots of possibilities to try. I looked on the internet to see if anyone has done any of these experiments already. Pot-in-pot growing looked similar but I didn't find enough published information to answer my questions. I will have to find out the slow way.

Summer will officially be finished in two weeks so I had better get busy.

Fountain grass

I have bought some new plants. I found purple fountain grass (Pennisetum setaceum Rubrum) in the Harmony garden centre. When I was in Canada last summer I saw lots of plantings featuring this grass and I fell in love with its dark leaves and graceful foxtail flowers. I have kept an eye out for it since I returned to Tasmania and was delighted to find it in stock at a local centre.

Finding it put me in such a good mood that I bought some other plants as well - some coral and yellow striped dwarf phormiums and a coral-blotched solanteum... whatever it is now, it used to be called coleus. These will be kept in containers and grouped with the similarly coloured Tropicana canna.

Another addition to this cast of all stars is Juncus filiformis Spiro. As I wire worker I find this plant has special appeal because its stems are all curled in loose corkscrew spirals. It is so attractive. My camera batteries are flat so I haven't photographed the new plants yet but will do so shortly.

Birds in the bush

The fruit on our plum tree was almost ripe when the birds discovered it. A news flash went out to all flying fructivores in the area and for the last couple of days the tree has borne a heavy crop of birds. Whenever I go into the garden I hear the twittering whistles of little green parrots or the quick soft gossip of silvereyes as they devour the plums.

I feel a bit disappointed that I won't get to eat many plums but not very disappointed. We have several types of fruit trees and always end up with a glut of something, so we won't miss the plums. More important, I am quietly delighted to have the birds. They are so beautiful and so clearly enjoying themselves at their plum feast. I think from now on I will simply consider that the plum tree is for the birds and its purpose in the garden is decorative. (If I get an occasional feed of plums it will be a bonus.) May I never need my plum harvest more than the parrots do. What is the real worth of a bird in the bush?

And I don't intend ever to put bird netting over the tree. I accept that orchardists do, but they enclose whole orchards with taut nets and birds do not often get trapped in that type of net. Loose netting is a different thing and can be hazardous to birds. Last night I heard about a cockatoo that had been entangled in netting for two weeks before being rescued. Other cockatoos had fed the captive bird during that two weeks which is an indication of what sociable and caring creatures they are. It is a pleasure to share my garden with them.

Here is a link to the story: http://www.abc.net.au/news/stories/2008/02/04/2153742.htm

Thinking about the strawberry tower

I say "strawberry tower" although what I have in mind is actually a hanging garden, a column of plant pots suspended one above another.

Several years ago, Geoff & I grew strawberries hydroponically in hanging tubes filled with perlite medium. No electricity was available on site so I watered them manually. They cropped satisfactorily, but only if they were watered with nutrient solution at least twice a day, and three or four waterings per day was better.

Growing strawberries in hanging containers is great - you don't have to bend down to pick them and they are out of reach of snails and other ground-based pests. The need to water them so frequently was a big minus, though. I don't want to set up an elaborate automatic watering system and I don't intend to hand-water 3 or 4 times a day, so I want to see whether putting a water reservoir in each individual hanging pot will solve the watering problem.

Simply hanging PET bottle planters in a vertical chain would meet the minimum requirements of what I have in mind, although if each planter had to be individually watered it would be very tedious. Ideally, I want to be able to water all the planter units in a column at once. Plastic tubing is going to be involved.

In spite of having to use a bit of plastic tube, the aim is to build planter units that re-use materials that would otherwise become landfill or go to be recycled. Construction must be simple, without the need to use special tools. If possible, I would like to find a planter unit that can be used for conventional growing using potting mix as well as for hydroculture. (Increased weight of potting mix will put greater demands on the suspension system. Potting soil could have possible drainage problems, as well.)

I have three different types of planter unit on the drawing board, and will try to have prototypes ready for planting by Monday so growing trials can get underway. More anon.

Low-tech High-performance Plant Pot

This simple do-it-yourself planter has a water reservoir from which water moves to the potting soil by capillary action. I use this planter for both conventional growing using potting soil and for a bit of hydroculture, and find it very useful. Here's how to re-use a plastic bottle to make one of these "self-watering" pots.

1. Gather the required materials.
You will need a clean, empty plastic bottle together with its cap, a pair of scissors, a metal skewer or nail, a push pin (drawing pin), and a small scrap of fabric or string to serve as a wick.

The general idea is that you cut the top section off the bottle, turn the cut-off part upside down, then insert the cut-off part in the bottle base so that the cap touches the bottom of the bottle. (See picture at Step 3). The top part must fit snugly inside the bottom part with no gaps around the edges where the potting mix would fall through, so cut the bottle at a place where the diameter of the top part will match the diameter of the lower part. Before cutting, you can check diameters with a piece of string if the bottle has fancy curves in it.

2. Cut the top part (the Head and Shoulders) off the bottle.
Use the push pin to make a row of 5 holes where you want to begin cutting. Make the holes almost touching each other so they will tear easily when you push the point of the scissors against the perforation. With the scissors, cut around the the bottle as evenly as possible.










Starting with the little perforations means that you are less likely slip with scissors and injure yourself than if you tried to hack into the plastic using only the scissors, and the perforations also enable you to position a cutting line with literally pinpoint accuracy.











3. Check that the top section fits snugly into the bottom of the bottle.
Invert the cut-off top section into the lower part of the bottle. If the cap does not touch the bottom of the bottle, then trim the top section along the cut edge until a snug fit can be achieved. (If the top section is too small - with gaps between its edges and the sides of the lower bottle - you can't fix it easily. Get another bottle and begin again. ;-)








4. Make airholes / drainage holes in the top section.
Use the push pin to puncture 12 or 15 holes randomly around the shoulder part of the bottle. Use the skewer or nail to make each hole a bit larger, but not so large that soil will wash through.



These holes will allow water to drain from the potting soil, and for air to reach plant roots.






5. Make a hole in the bottle cap.
I do this directly with the skewer without "predrilling" with the push pin. I put the bottle cap on the concrete floor with the cap's top facing upwards (so it looks more like a table than a cup, if that makes sense) and just stab it. If the bottle cap you are using is very tough then you might have to use a hammer and nail - or a drill, of course, if you have one handy, but these instructions are intended to be low-tech.

6. Poke the string or fabric through the hole in the bottle cap.
The wick in the photograph is polyester fibre recycled from an old cushion. Many materials could be used to make a wick - string, a short length of old pantihose, or a strip of fabric about 1 centimetre wide and 3 or 4 centimetres long. The wick is not strictly necessary but is useful because it can retrieve the last drop of water from the reservoir. Most plastic bottles are not completely flat-bottomed, and the centre area where the bottle cap rests is higher than the edges, so when the reservoir is nearly empty the bottle cap will not be in contact with water unless a wick is used.

The skewer is all I have ever needed to push the wick through the hole but sometimes it has taken a bit of twiddling. A small crochet hook might be helpful.


7. Screw the bottle cap on.
The cap does not need to be screwed very tightly. I leave the cap loose enough so that water can enter here as well as through the wick, for built in redundancy of the water supply.


This part of the planter is now assembled.








8. Cut an overflow hole in the side of the bottle.
About 4 to 5 centimetres (1.5 to 2 inches) above the bottom of the bottle, pierce a row of 5 closely spaced holes with the push pin. With the scissors, push into these performations and cut a small hole in the side of the bottle. Make the hole approximately the same diameter as your fingertip.
The size and shape of the hole doesn't matter, although its position in the side of the bottle is important. If it is low, then the reservoir will not hold much water and will have to be refilled more frequently. If the hole is high, then the potting soil will not drain well - although you may want that if you plan to grow a water-loving plant in the pot.






9. Invert the bottle top and fit it into the bottle base.
Now you can fill the container with potting soil and plant something.


These planters are excellent for starting seeds or cuttings because they keep the potting soil uniformly moist, which means fewer failures caused by either drying out or overwatering.








Watering
In cool weather and with smallish plants, these planters contain enough water to last at least a week without needing to be refilled. However, in summer I refill mine every fourth day. I think that mosquitoes could possibly breed in the planter reservoirs and I want to prevent that. So every fourth morning I tip out the old water from each planter, allow them to dry out for an hour or so, then refill with clean water. I refill by lowering the planter base-first into a bucket of water. Water flows in through the overflow hole and fills the reservoir to the correct level, so I don't have to measure the amount of water added to each planter. If you were to use these planters to grow indoor plants, I am sure that you would not have to refill for at least a week.

Don't like the bare bottle look?
It may be desirable to cover the outside of the planters. Plant roots may need to be protected from overheating caused by sunlight shining through the clear plastic walls of the planter. The plastic may break down when exposed to ultraviolet light from the sun. I am trialling several materials as covers for planter bottles. The most successful so far has been aluminium foil but I also like recycling potato crisp packets and other bags made of shiny "metallised" plastic. I cut the top and bottom off one of these bags to make a sleeve the same height as a planter then slip the sleeve over the planter. The fit should be loose enough to allow easy access to the overflow hole, and snug enough so the cover won't blow off in a breeze. The bags seem to make excellent covers but I have only used them for a few weeks and don't know how long they will last when exposed to strong sunlight.

Recycled gift wrap (plasticised type) might also make good covers, as might waxed cardboard boxes, old plastic tablecloth, and leftover building materials such as paint, waterproofing membranes, or vinyl sheets. Fastening a sheet of material around a planter is probably best done with string or ribbon unless you have a good quality sticky tape, because the adhesive in cheap sticky tape seems to break down quickly.

Planters can be grouped in a tub, box or basket for an attractive display in which the pots do not need individual covers. There are lots of low-cost possibilities for decorative covers so your garden or patio does not have to look like a bottle recycling centre (unless you want it to).

I like this type of planter so much that I am working on extending the idea. I am devising a strawberry tower / herb tower from plastic milk bottles, using the same water well principles. This time I will try to make the water reservoirs mosquito-proof, so am still working on refining the basic design but will post results fairly soon. Watch this space.