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Latest posts by BobTheGardener

Raised beds with decking boards

Posted: 13/04/2013 at 22:59

Hi Lorraine, That is an old article.  You can no longer buy pressure-treated wood containing arsenic and chromium as they have been banned for such use.  It doesn't help that authors of articles on the web rarely put a date on them!  Here's a more up to date one:

Just about everyone (including me) uses pressure-treated softwood timber for building raised beds and planters as untreated wood will rot in very short order, unless it is one of the more rot-resistant hardwoods, such as oak, cedar or redwood etc.  Those are all prohibitively expensive for many of us though.

Your idea of lining it with polythene is a good one.  I would also recommend painting it with a water-based wood treatment such as fence paint.  Look for a waterproof one as that will help seal it against any possible leaching of the miniscule amounts of copper which are used in the pressure treatment.

Growing Under Plastic Sheeting

Posted: 13/04/2013 at 18:56

I agree, nutcutlet.  It is useful to help with the initial clearing of a badly weed infested patch, but hand-weeding will always be necessary and is the best way.  I especially don't agree with the permanent laying of membrane as some councils and builders do as it just goes against nature, ruining the soil and natural soil ecosystem (eg starving worms for a start.)  I much prefer using a good depth of mulch as this suppresses weed seedling germination and the perennial weeds are easy to see so can be removed as soon as they poke their heads through.  A mulch will also feed the soil with little need to provide any extra feed. Win-Win.

Growing Under Plastic Sheeting

Posted: 13/04/2013 at 18:29

Many will have recently germinated from weed seeds in the soil because the sheeting has helped warm the soil up.  Others will be perennial weeds like dandelion which start coming up at this time of the year.  Because they will be unable to photosyntensize due to lack of light (I presume they are mostly white/yellow in colour?), they will die as long as you leave the sheeting in place.  To kill all weeds using weed suppressing membrane, you may need to leave it in place for a whole season.  As soon as you plant anything or turn the soil, dormant weed seeds will be brought to the surface though, so membrane is not a panacea.  There's an old gardeners saying that goes "One year's seed is seven years weeds." which is effectively how long it takes of diligent weeding before an area is as weed free as it is possible to make it.

If you have plants ready to go in, I would suggest making slits in the sheet and planting through it for now.  You could hide the sheet with bark chippings for the time being.  Keep peeking under the sheet and when the ground is clear later in the year, remove the bark and cut the rest of the sheet up (so you don't damage anything you have planted) to remove it.

old greenhouse uses??

Posted: 12/04/2013 at 00:41

Hi LeighAnne, is it an aluminium frame?  If so, the glass is held in with wire clips.  Be extremely careful though as old horticultural glass is very brittle and tends to easily break in long extremely sharp pieces when handled, so you need to be well protected all over your body.  If the frame is undamaged, it would be possible to reglaze it, perhaps with polycarbonate replacement panels as those are child-safe.  If you advertised an aluminium framed greenhouse on freecycle as "free but must be dismantled by collector and all broken glass taken away", I have no doubt it would go to a good home and you wouldn't have to pay someone to dismantlle/dispose of it for you.

Old rotten wooden greenhouses are a different matter.

Seeds are up

Posted: 11/04/2013 at 23:28

Lots of stuff sown in the cold greenhouse popping up now.  Cosmos the fastest of those - 4 days.  It's a good job as I have absolutely no space left at all now on windowsills or in the conservatory.  The only no-shows so far are celeriac and nicotiana suaveolens, but the latter came with double the number of seeds as the supplier had noticed low germination rates in testing.  Can't say either will be missed if they don't germinate.

Herb border

Posted: 10/04/2013 at 22:03

Hi garjobo, one of the cheapest ways to build one is using decking boards (Wickes have a 25% discount on at the mo.)  You need to drive in 2" (5cm) square stakes of treated timber into the ground at the corners and about every 18" (40cm) along the sides, to hold the weight of the soil.  Best to use stainless steel or plated 2" (50mm) screws, or galvanised nails.  Drive in the corner posts first, taking care to keep them vertical then you can measure the boards and cut them to fit.

Bee spotting

Posted: 10/04/2013 at 21:46

Hi Gardengirl, I think the first one might be a carder bee, but there looks to be at least 3 different types in your photos, so very encouraging!

Bee spotting

Posted: 10/04/2013 at 21:19

Hi Rain, I've steadily been building up a variety of plants over the years to try and make sure there's always a bee-friendy one in flower.  This is the RHS by-season bee-friendly plant list:

It's quite long so I'm sure there're plenty of ideas to suit all planting schemes.


Herb border

Posted: 10/04/2013 at 21:04

Make sure the bed is well-drained as most herbs prefer or even require this and many will not thrive in heavy and certainly not even slightly waterlogged soil.  You can do this by mixing in plenty of grit, sharp sand and/or perlite.  I like the idea of a Bay tree at the back.  They are slow growing so won't take over.  Rosemary is also evergreen and lives quite a while if it is happy with soil conditions.  Sage has lovely blue flowers and can also last for several years if cut back when it gets leggy.  Bees go crazy for any of the thymes. Oh, and if you like basil, there are lots of varieties with coloured leaves which can be very decorative planted at the front, but are annual and die at the first hint of frost. 

Jet Stream finally moving up

Posted: 09/04/2013 at 22:36

Hoping for a bit of rain here, too, hollie hock (hopefully at night, of course!)  Had to water all of my outdoor pots at the weekend - pretty unusual at this time of the year.  My water authority (ST) are telling customers to be careful with their water use.. and that after the 6 months of deluge that passed for last "summer"!

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1 to 15 of 25 threads