Even the most well balanced and eco-friendly garden requires
a bit of pest control. I am finding that a lot of people ask about how to
tackle insects that are eating their non-edible leaves of plants like root
vegetables, tomatoes, beans and radishes. As these plants are grown for things
other than their leaves there really isn’t any need to take any action. If
pests are eating your broccoli or munching their way through your favourite ornamental like a hosta or begonia then you might need to take a bit of
evasive action to keep the damage to a minimum.
I have what I think is one of the easiest and most versatile
of solutions. Rhubarb .
Rhubarb doesn’t just taste delicious; amongst other things,
the leaves of the plant can also provide a natural pesticide for your garden.
Rhubarb.
(Rheum rhabarbarum), is easily grown here as we have a cool
climate. The plant itself originated in Asia over 5,000 years ago and was
initially cultivated for its medicinal qualities.
Rhubarb has been used for centuries in traditional Chinese
medicine. The dried roots of the plant are used to treat a variety of ailments,
including constipation, liver and gallbladder complaints and poor blood
circulation.
Rhubarb Pesticide
Rhubarb leaves are poisonous and contain oxalic acid which
is highly effective in the garden. The oxalic acid in the leaves can help to
control aphids, particularly on roses.
The recipe here includes soap, which I personally won’t use.
It is added as a surfactant to spread out the liquid on the leaf but I don’t
think it needs it. Dogs might lick the soap solution too and it won’t do them
any good.
What You’ll Need
- An old pot, stirring spoon that won’t be used again for food preparation.
- A clean bucket and a spray bottle.
- Water
- Dish detergent or soap flakes – do not use laundry detergent
- Storage jar or bottle
Method
- Trim the stalks from the leaves.
- Put the leaves into the pot.
- Bring the leaves to the boil and then reduce to a simmer for 30 minutes.
- Strain the solution into a clean bucket.
- Discard the leaves in your compost.
- Pour the strained solution into a spray bottle.
- Add 1 tspn of the detergent.
- Label as ‘POISON’.
Using Rhubarb
Pesticide
Use this pesticide for controlling aphids, slugs and caterpillars
that crawl on the leaf of your decorative (non edible) plants.
It might be a good idea not use this pesticide on edible
crops. Though a good wash may remove the poison, I would not recommend testing
it.
Remember though that this method is a last resort in the
garden. Healthy plants are much less
susceptible to damage from insects. So remember to feed the soil every year
with well-rotted manure and compost.
Other uses for
Rhubarb
Rhubarb isn’t only for pies and making a spray though. Here
are some other uses for this versatile plant.
Cleaning pots and
pans
Use Rhubarb to clean your pots and pans. If your pots and
pans are burnt, an application of rhubarb over the afflicted area will bring
back the shine in next to no time.
Hair Colour
This is a fairly strong dye that can create a more golden
hair colour for persons whose hair is blond or light brown. Simmer 3 tbsp. of
rhubarb root in 2 cups of water for 15 minutes, set aside overnight, and
strain. Test on a few strands to determine the effect, and then pour through
the hair for a rinse. Usual disclaimers apply – I’m not responsible for the
outcome!
Making paper
The fibre in rhubarb is a nice additive to handmade papers.
Rhubarb planting
Rhubarb needs an open, sunny site with moist, but
free-draining soil and doesn’t like being waterlogged in winter. Avoid frost
pockets as stems are susceptible to frost.
It can be grown from seed, but it's more common to plant
dormant year old crowns between autumn and spring. Prepare the ground by some
well-rotted manure, then spread out the roots and plant so the tip of the crown
is just visible above the soil.
Pot-grown rhubarb can be planted at any time, but will need
plenty of water during dry spells. Space plants 75-90cm (30-36in) apart, with
30cm (12in) between rows.
Rhubarb can also be planted in very large pots at least 50cm
(20in) deep and wide.
Harvesting
Harvest the second year after planting as this will improve vigour.
Remove a few stems for usuing but try to
leave some to keep the plant in active growth. To remove, hold the stalk at the
base and ease it out of the ground, aiming to avoid snapping it off. Although
rhubarb stems remain palatable and usable through summer, it is best not to
over crop the plant and end pulling by June. You can always sneak a few extra
off as the season moves on.
