Greenhouse Shelving, Benches and Lighting
20th Feb 2003
It's that time of year when my greenhouses are starting to get really full once again. You always assume that you are going to have plenty of room, but before you know it, you are struggling for space. This of course is certainly not desirable as you then tend to push plants far too near to each other with the consequence that they end up being drawn and leggy.
Have a good think of how you can utilise space within your greenhouse. There are many different designs on shelving that you can now purchase, some are permanent others actually fold away.
Another good idea is to utilise the area underneath your greenhouse benching. In my case, it"s an area where I store some pots and compost so that the latter will always be the same temperature as the growing plants. Obviously to just stick some extra shelving directly underneath a bench is not going to be very clever as the light getting to the plants will be very minimal and therefore a waste of time.
You can though still make use of this area as a very effective space indeed, rather than having your artificial lights above the bench, have them installed underneath it and thereby instantly giving yourself double the space that you had. The lights needn't cost the earth either, contact a demolition contractor and ask him if he has some salvaged fluorescent fittings that you can buy. The tubes may be broken so you may need to purchase the ordinary 'warm" tubes. A bank of six of these next to each other, to cover the width of three feet, would give you some pretty effective extra growing space.
I was nearly caught out once more the other day when I checked if the sand underneath the trays and pots of onions and leeks was moist and warm. It was certainly warm but very close to being far too dry; as I have mentioned before, it's crucial that the sand is kept moist at all times. Failure to do this will mean that once the moisture has been depleted from the sand, the warmth from the cable will then start to dry out the compost in the bottom of the pots consequently burning out the roots.
Initially I give the bench a thorough soaking of water, using a hose-pipe and lance making very sure that the water permeates right through to the very bottom of the propagating bench. Throughout the growing period on the bench, it's critical that the moisture level within the sand is monitored regularly, It will pay you to check it while the plants are growing on a weekly basis. As the whole of my bench will be full of trays and/or pots, it's impossible to remove them all, I therefore take out a couple of trays at a time, then soak the sand thoroughly. The water will permeate right through the sand by capillary action.
During early January, at the far right hand corner of my growing cabinet, I had my own selection of the Kelsae onions in 7 inch pots for the production of seed. All of you that follow my column will know full well what a disaster I had last year with my large onions. A high percentage of them bolted, as I wasn't able to plant them at the right time and they became severely pot bound. However all was not lost, friends of mine who grew their onions using my seed kindly gave me some of their resulting bulbs back; my thanks therefore to Brian Rance, Ken Davies and Bill Jones for helping me out.
By placing the big onions on to the warm sand the new root system develops fast, as soon as some green foliage is seen as well as some white roots at the bottom of the pots. They have now been removed from the growing cabinet and placed on an adjoining bench. These will be planted out around the end of March to produce seed during July and August in my onion polytunnel, the beds will have had soil warming cables buried prior to planting them.
Giant vegetables rarely impress me when I see them at various summer and autumn shows, but when I was invited to visit the garden of Peter Glazebrook from Halam Newark last August, I was spellbound. Never before had I witnessed so many different types of vegetables being grown to such gigantic proportions and with so much loving care and attention. The cabbages in particular were not only enormous, they also possessed superb quality. If you want to have a go at growing a very large type, then you must sow the seed straight away if you are to have any hope of winning with a very large cabbage at your local show.
I have no idea what variety Peter grows but I do know that 'Brunswick', which is available from my current seed catalogue, will certainly grow to a very large size. So big in fact can this cabbage grow that every packet should carry a health and safety warning!! you will probably need a wheel barrow to get it into the show venue.
Space out the seed on top of some seed compost in a half size tray, press down into the compost and cover over with some fine vermiculite and water. Place in a propagator for an even and quick germination, when the seedlings are through, remove the tray and place on a bench in the greenhouse with a minimum air temperature of 50°F. As the cabbage is starting to show it's first proper leaf transplant them into 3 inch pots using some Levington M2 and repeat this process of potting up until the weather has settled sufficiently to plant them outside during mid April into well manured soil.
I hope to write a special article on Peter later on this year covering most of his growing techniques.