Plant growth in a box

Photo credit: Instructables

Small Indoor LED Plant Grow Room

Since my light covers almost the entire top of the box I cut a hole in the entire top except for the side with a flap (left an inch or so) and the corners to keep some strength in the box. -
Since my light covers almost the entire top of the box I cut a hole in the entire top except for the side with a flap (left an inch or so) and the corners to keep some strength in the box. –

I have done a few indoor gardens before, mostly because the weather in Michigan does not allow for a very long season. I recently moved to Phoenix and tried container gardening outside and was disappointed in the amount of pests that decimated my small container farm. So here is my take on a very small indoor LED garden to see how it works out.

Read the full article: Instructables

Indoor Plants in Winter

Photo credit: The Record Herald

Rosemary in window-Turn 1/4 every few days to keep growth even (B.Petrucci)

Winter Care Tips for Indoors Plants

by Carol Kagan, Master Gardener


From Master Gardeners I have learned a few key things, so here is my quick tip list followed by a number of great resource sites. It is important to check the needs of each plant since they can vary greatly.

Aloe roots crop -
Aloe roots crop –

1. Be sure the plant is potted in the right size container (with a drainage hole) and right potting soil.

If you are digging it up and dragging it in from the outdoors then potting it up, don’t use garden soil. It’s too heavy.

2- Water only as needed when the soil is dry.

Water from the top until water comes out the drainage hole (You do have a drainage hole, right?) into the saucer. About two hours later, drain any excess water from the saucer. Don’t allow the roots to stand in water. If you don’t see drainage but have watered well, check for a clog in the hole and clear it. Inconsistent watering is one of the primary reasons for plant loss.

3- Use room temperature water.

Leave tap water out overnight, uncapped or uncovered, to allow the chlorine and fluorine added to city water to dissipate. Although these probably don’t harm plants, you want the water to be at room temperature anyway. Rainwater, snow melt and well water are ok. Don’t use water run through water softeners.

4- Light should be appropriate for the plant. – See more at:

Plastic bottles and bags: precious jewels for container gardening (Willem)

On September 12th, 2007 Riziki SHEMDOE sent the following message :

“I have been reading on the container gardening experiments that you have been doing. This has encouraged me to put up a proposal on introducing this technology to the rural semiarid areas of Tanzania where normally crop production is very poor due to drought and poor soil fertility. I am requesting to know whether there are some best practices from the third world countries that you have come across regarding the use of this technology in improving rural food security and poverty alleviation? I will be grateful if you share with me some of the best practices so that I may use them to strengthen my proposal. I look forward to reading from you.
Kindest regards,
Riziki. “

Riziki Silas Shemdoe (MSc)
Institute of Human Settlements Studies,
University College of Lands and Architectural Studies
P.O.Box 35124 Dar es Salaam, Tanzania

Here is my reply :

The easiest and most practical way for people in developing countries to practice container gardening is to collect a large number of plastic (PET) bottles and plastic shopping bags. It’s clean and cheap. Moreover, it helps to take care of our environment !

The plastic bottles should be cut in two : a shorter bottom part (the cup, used as a water tank) and a longer top part (with the stop still on), to be filled with potting soil. In order to cut the bottle in two optimal parts, define the length of the two parts approximately so that, turning over the top part (that will contain potting soil later on) and sliding it into the bottom part, the stop is touching or almost touching the bottom of the cup. If this is not the case the bottle will be rather unstable. Then, a small slit should be cut at the edge at two opposite sides of the bottom cup so that the top part of the bottle can be pushed into the cup until the stop reaches the bottom (short slits will open a bit). It is better to have the bottom cup a bit too long than too short (stability). One can always cut the two slits !

The bottleneck should be perforated at two opposite sides, close to the stop, to create drainage possibilities if too much water is poured in the bottle and to create water absorption possibilities from the bottom cup. Holes of 5 mm diameter are sufficient.

When filling up the inverted top part with potting soil, the soil should be well compressed in order to avoid larger air cavities in the bottle. I recommend to mix a water stocking soil conditioner with the potting soil, but if this is not possible for financial constraints, don’t hesitate to do it without.

During the first days, watering should be abundant to eliminate too much air in the potting soil. As the infiltrating surplus of water will run through the two openings in the bottleneck into the bottom cup (water tank), and as evaporation will be limited (only through the top opening of the bottle), one can save a lot of irrigation water and produce significantly more biomass with less water (less leaching of nutrients from the potting soil, and less evaporation).

Isn’t this a nice solution for some of our main environmental problems in the drylands ?
The same advantages are offered when growing vegetables or young trees in the classical plastic shopping bags.

Fill up a plastic bag with potting soil for 2/3, and keep the two handles of the bag upright, simply by pushing them up and sustaining them with two pieces of a small branch or another support (one at each side of the bag). Thus, a shallow cavity is created above the potting soil in which water can be poured from time to time.

Don’t forget to perforate the lower part of the plastic bag a couple of times at the two opposite sides of the bag, e.g. 2-3 little holes (not slits !) at both sides approximately 1-3 cm ( 0.5 – 1 inch) above the bottom (and not in the bottom itself, so that a bit of water can be kept temporarily in the bag). Vegetables can be seeded or planted in the potting soil. Young tree seedlings can also be grown in such a simple plastic bag.

Considerable advantages :

(1) more biomass with less water (because of less leaching and less evaporation).

(2) eliminate plastic from the environment by burying the used plastic bottles and bags at the end of the growing season, e.g. when planting the tree seedlings in a planting hole (ecological cleaning).

Caution : avoid heating in the bottles or bags by keeping them in half-shade or in places where the number of hours of sunshine is limited (not a full day).

Please set up some experiments and discover the real advantages of gardening in plastic bottles and bags, not in the least the provision of food security and the alleviation of poverty. That’s what I call a success story or best practice for sustainable rural development. I hope that once my preaching in the desert will be heard.

PS. Have a look at my former postings to discover pictures and drawings.



“Thank you so much, Prof., for the explanations and the methodological approaches. I will try something in this area. This will really relieve our poor people in the dryland-areas to improve their nutrition. Similarly this will assist in improving the environmental sanitation by giving use values to the plastic bottles that are being thrown everywhere in our cities. Thank you.

Non-flowering strawberries in window boxes (J. TOLLEDOT)

Here is a question coming from my friend Joseph TOLLEDOT :

“I remember you had a flowering and fruiting Strawberry plant in a bottle…I planted some 10 bare-root Strawberry plants in March in window boxes – only one plant flowered and gave some fruit only once and then stopped. All the others have produced plenty of healthy leaves and many runners but no fruit – very disappointing! – What can I do now? Any ideas? I have seem much contradictory advice on the internet so I am unsure what to do!”


Joseph referred to my former posting:

My very simple strawberry bottles (Willem)

Strawberries flowering and fruiting in plastic (PET) bottles

I don’t have see a clear reason for the fact that Joseph’s strawberries are not flowering in the window boxes.  I can only make a couple of suggestions :

1. Can it be that temperature is sometimes becoming too high in the boxes?

2. Can it be that inside the boxes (behind the window) there is a lack of UV rays?

Who can help us out ?


Growing Chillies in pots or grow-bags (Gardening Patch)

Read at :

Gardening Patch

Growing Chillies – advice on how to grow Chillies

Growing Chillies requires a warm growing environment and so unless you live in a warm climate your Chillie plants will spend a considerable amount of time indoors or in the greenhouse. Chillies are most often grown in pots or grow-bags and are a good source of vitamin C. They also stimulate the circulation and boost metabolism so give a feeling of energy. Chillies are very similar to sweet bell peppers (Capsicum) but they have a hot fiery flavour instead of the sweet flavour associated with bell peppers. Continue reading Growing Chillies in pots or grow-bags (Gardening Patch)

Containers : black, white and transparent (Willem / Italman)

Here is an interesting reaction of Italman :

I’m very interested to see the results of your experiment. By the way, currently I’m experiencing some troubles with my plants that are in black pots. It’s extremely hot these days and I suspect that the roots are boiling. I’ll be painting those white for next year!

More research work seems needed to decide what should be the colour of our containers, grow bags etc.  Should it be white to reflect the sunlight and keep the roots cooler ?  Can we use without any problems transparent containers in tropical regions ?  What is the ultimate effect of the development of algae inside the transparent containers ?  Are black containers OK in tropical regions ?

A lot of questions to be answered !

Transparent containers or not ? (Willem)

Yesterday, I raised the question about possible negative effects of transparent containers on root growth (see my posting :

Is sunlight affecting root development in plastic bottles ?

in which I mentioned that Joseph TOLLEDOT  and I did not encounter any problems when using transparent bottles.

Today, I found an indication on the following website :

Grow Bags – 1 Gal Grow Bag $0.39

These disposable plastic grow bags can take the place of regular more expensive pots when short term growing is anticipated. They are made from 4 mil heavy plastic. They come in 4 different sizes. They are black on the inside and white on the outside to reflect light back to the plants while maintaining healthy root temperatures. They are fluted, so that they stand straight up when filling and have pre-punched holes on the bottom for drainage.


It sounds logic that temperatures in transparent containers are higher than in non-transparent ones.  However, I doubt seriously that differences between the classical black containers (like the plastic grow bags used in nurseries) and our transparent plastic bottles will be significant.

Nevertheless, I take the point mentioned above about the grow bags :

“They are black on the inside and white on the outside to reflect light back to the plants while maintaining healthy root temperatures”.

Light reflection on the white outside will keep the temperature inside the bags lower.  This gives us an indication that, when covering our transparent plastic bottles (with paint or aluminum foil), we should choose light reflecting materials.

Is sunlight affecting root development in plastic bottles ? (Willem)

Root development in transparent bottles

The question about the possible negative effects of the transparency of plastic bottles on the root development keeps our attention.

Here is Joseph TOLLEDOT’s reaction:

I also have not noted any negative effect of transparent bottles and, as you (Willem) have seen from my photos, they are growing well. I did read somewhere that the very fine root hairs which as so important for water uptake can easily be dried up by the sun during Summer and this makes sense but I have not really noted a problem myself. A simple solution would be to spray paint the outside of the bottles.

Have a look at Joseph’s nice pictures on:

and look at the excellent growth of the plants.

I am cultivating myself a number of plant species in small and large transparent plastic bottles (see former postings) without any problems. I will now cover some bottles in different ways (spraying paint, like Joseph suggests, using aluminum foil, etc.).

Look out for my results in a few weeks.

Young walnut treeA young bambooPapaya seedlingStrawberriesArgania seedling
(1) Young walnut, (2) bamboo, (3) papaya seedling, (4) strawberries, (5) Argania growing well with roots in full sunlight.(Click on the pictures to enlarge them).

Garden where you can (Urban Growth)

Read at :

Urban Growth

Friday, July 20, 2007

Garden where you can

Even though my balcony garden plants get the most of my attention, my balcony isn’t the only place where I grow plants as I’ve already mentioned. I have some plants in my apartment, as well as in front of my apartment and on the stairway, growing in bunch of containers. For every urban grower space is one of the greatest limitations, but there’s always a way! I garden everywhere I can and even in some places where that seemed impossible at first. You have to be creative and do a lot of experimenting, but in the end it all pays back! There’s usually not a lot you can do regarding the conditions (amount of sun, temperature, air movement) you’re faced with, so you’ll have to take care good care while you choose where to grow certain plants. For example, I have a few cherry tomatoes on my stairway (inside of my apartment building) that are growing very slowly, while those on my balcony garden grow as crazy. I guess you would assume it’s the lack of light that’s causing this, but it’s not, it’s the lack of air circulation and very high temperatures. Something I can’t change, even if I wanted to. However, although such conditions aren’t favorable, some of my urban grow plants seem to grow there quite well.

Bottle gardening : Italman’s comment (Willem)

Yesterday, I received the following comment :

Hey Willem,
Thanks for including my experiences into your blog. I appreciate the effort and hope you’ll keep up doing good work. Each one teach one!
Regarding the plastic bottle idea, I’ve tried it myself and it works fine.  However, I read somewhere that it’s not good for roots to be exposed to light, so I used to cover up the transparent bottles! That sounded pretty logical to me, because roots naturally grow in the ground, where there’s no exposure to light. What do you think?

Thanks for the appreciation.

Concerning roots exposed to light in transparent bottles : I always used transparent bottles and did not observe negative effects on the the roots.  Of course, a lot of algae develop inside the bottles.  However, I don’t see any problem for the plant growth.  I suppose there could even be some positive effect, particularly with development of blue algae (nitrogen).

I wonder if literature is telling us something about this.  I will try to look it up on the internet.

If needed, we can always apply your suggestion and cover up the transparent bottles, e.g. with aluminum foil.

Let’s look for the best solution !