GreenHouse Report 01/29/2013
Written by: Melanie Newfield, Mission Specialist Biological Sciences

I watered all the plants in the greenhouse, but since it wasn't sunny, things weren't dry and I didn't need to water so much.

I did some rearranging, moving the 4 trays of cress seedlings over to the table next to the head pad, so that I had a suitable space to work on.

I took the cuttings that were in the hab out to the greenhab to repot, as many looked dead and there were some initial signs of mould in one pot. THe two lots potted in
round tins had no drainage holes, meaning that they were very likely to rot, and the humidity in the hab is probably not going to be high enough to keep the plants moist above ground.

I found that some of the oregano cuttings had leaf regrowth and signs of roots, and I think that there is a good chance that some will survive. All the aboveground parts of the thyme were dead, but below the soil they were still green. So I repotted all the ones that had signs of life. The rosemary was in the same condition and I repotted that. The remaining plant (not sure what it was) seemed to be mostly dead, but I repotted most of them anyway. I also skuaed* some plastic bags from the kitchen to make little covers to keep the humidity up around the cuttings.

I also skuaed a few supplies from the junk pile. Some of these may prove useful and some may not - anything that isn't useful in the green hab will be returned to the junk pile. Skuaed items are:
- a 40 litre rubbish bin and lid for water.
- 3 15 (?) litre buckets for putting old potting mix in (any potting mix that has had signs of mould shouldn't really be reused, but if there are cost constraints I will dry it and leave it
outside to try and kill anything in it)
- compost sifter (mesh on a wooden frame for getting the finer compost for seeds)
- 2 saucers for pots
- fine mesh to make a cover for pots
- a small piece of wood for smoothing down soil

I've had a few ideas for things that could be done differently, or different products that could be purchased. All the bags of soil are really intended as compost for enriching the soil when planting plants in the ground. If possible, I'd recommend the following products (although they may have different names in the US - when I have internet access I'll check):
- seed raising mix. This is a fine potting mix, with a low nutrient content and fungicide added.
Both the fungicide and the low nutrient levels discourage fungal growth.
Fungicide can be contained by ensuring that no soil or water that drains off the plants is introduced to the environment (or organic seed raising mix can be used if you don’t want to introduce pesticides)
- standard indoor potting mix. THis is basically a compost with slow-release fertiliser granules and pumice for improved drainage
- pumice, river sand or vermiculite. These products contain no organic material and are inert.
Cuttings are best grown in an extremely low-nutrient mix like pumice, sand or vermiculite to discourage fungal growth. These materials can also be added to other mixes to improve drainage.

If you don't want to waste the current potting mixes, it would be possible to mix them with pumice and some slow release fertilizer granules and use those (I'd recommend leaving out the fertilizer for the seedlings though, and maybe using sand instead of pumice). This would be as good as buying a bag of potting mix.

In addition, I’ve had some ideas about quarantine procedures for the hab, but I’ll probably include that in my risk analysis if that’s ok.

I’ll keep repotting seedlings tomorrow.

I hope this report doesn’t sound critical with my wishlist and comments about things that could be done differently. I love the green hab and I’m very grateful to the people who have taken the time to care for the plants. Looking at some of the cress seedlings, the chard and the brassicas, I think that we are going to be able to have a lovely salad when we are in sim. I’m quite excited about the prospect!

*skua (verb, Antarctic origin), to scavenge or scrounge, especially something that someone else has discarded.


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