How to grow Rhubarb
How to grow Rhubarb - Description
Although rhubarb is typically eaten as a dessert, it is actually a vegetable since the fruits are not eaten.
Originating from Siberia, rhubarb is completely hardy - in fact exposure to frost is essential during the winter if it is to grow to its best.
Rhubarb is an ultra-low maintenance perennial crop and can be left completely to its own devices all year, however for best results a little effort goes a long way.
Its crop is produced from crowns consisting of fleshy rhizomes and buds.
Following a season of growth the rhubarb crown becomes dormant and temperatures below 5 °C (40 °F ) are required to stimulate bud break and subsequent growth.
The first shoots to appear in the spring are edible petioles and leaves.
These emerge sequentially as long as temperatures remain cool, i.e. below 32 °C (90 °F).
As temperatures increase, top growth is suppressed, even appearing dormant in periods of extreme heat.
With declining temperatures in later summer, foliage growth resumes.
Growing Rhubarb is relatively simple in cool climates and unlke most vegetables rhubarb is a perennial and so can be left in the ground and will return a crop for many years (around 10 to 15 years).
Rhubarb is quite a hardy crop and is able to withstand lack of water.
Apart from applying fertiliser rhubarb will survive and produce good yields with little other tending.
How to grow Rhubarb - Crop Rotation
Rhubarb requires a permanent site outside the rotation system.
Rhubarb it is a member of the Beetroot Family and it is recommended that it should not be grown in soil that has raised a crop of the same family in the last three years.
How to grow Rhubarb - Site & Soil
Rhubarb will grow well in part shaded areas.
Rhubarb does not grow well in high temperatures.
Avoid positioning in frost pockets.
Rhubarb can be grown in acidic soils down to about pH 5.0 but grows best in slightly acidic soil i.e. pH 6.0 - 6.8.
Rhubarb tolerates most soils but grows best on fertile, well-drained soils that are high in organic matter, such as well rotted manure or compost.
If the soil is not well drained then waterlogging can result in the crowns rotting.
How to grow Rhubarb - Soil Preparation
It is advisable and worth the effort to prepare the soil adequately before planting as the rhubarb will rely on the soil for a number of years to come, not just this year.
Dig the soil to a good depth and introduce a high level of well rotted organic matter such as manure or compost into the soil to provide nutrients and a good soil structure.
Do this about a month before planting to allow time for the soil to consolidate.
Make sure to remove as many weeds as possible as rhubarb doesn't like to be disturbed once established and so avoiding heavy weeding at a later stage is preferable.
How to grow Rhubarb - Cuttings & Offsets
Rhubarb is best grown from rhubarb crowns rather than growing from seed.
Rhubarb should be planted in early spring and requires low temperatures (around 40 deg F) for it to break its winter dormancy and renew growth.
Crowns should be planted about 10cm below the soil surface with the crown bud about 2 inches below the soil surface.
Any young shoots that exist should just break the soil surface.
Spacing of the crowns will depend on variety but around 60-80cm is right for many varieties such as the popular Victoria.
How to grow Rhubarb - Cultivation
Rhubarb responds to good care and watering.
Remove the flower stalks as they are seen.
Fertilize each year and cultivate shallowly as often as necessary to remove weeds.
Rhubarb responds well to fertilizers.
The quality of the crop harvested depends to a large extent on the care and fertilization received.
Give each plant 1 cup (about 2 handful's) of Growmore (7-7-7) fertilizer, or Blood Fish and Bone if you want to stay organic, each spring applied in a circle around the plant when growth starts.
Manure is an extremely valuable source of organic matter as it helps to conserve moisture, preserves the soil structure, and makes nutrients readily available.
Apply one to two shovels per plant for home gardeners.
An application of composted manure or leaves is beneficial in late autumn and early winter, but do not cover the crowns as this may promote rotting.
Fresh manure should not be used as this will burn the tender rhubarb plants.
A severe frost will have a damaging effect on rhubarb and may cause the oxalic acid from the leaves to enter the stalks.
For this reason you should remove any stalks that have been effected by a hard frost and place them on the compost heap.
The oxalic acid will be broken down successfully by decomposition on your compost heap.
You may want to thin your crowns every 4-5 years if they are getting overcrowded or you wish to use part of the crown to start another plant.
To do this carefully dig up the crown and then divide the crown into sections ensureing that you have at least one bud and two inched of root on each section.
You can normally obtain about 4 to 8 new root sections from a crown.
Rhubarb crowns should be split in early spring when new growth is just visible.
How to grow Rhubarb - Harvesting
Harvest rhubarb either by cutting the stems at soil level or by pulling up the stems.
You can harvest about 3 or 4 stems at a time per plant whilst leaving some stems remaining to generate the plants energy and growth reserves.
Do not harvest the plant in the first year as the nutrients produced by the leaves should be channelled back into the roots to ensure a strong root system for stem production in the following years growth.
In the second year harvest a couple of stalks per plant and after that you can harvest as normal.
The harvesting season can be extended by 'forcing' the rhubarb.
Rhubarb can be forced in winter by covering the crowns with large pots which prevent light reaching the crowns.
Forcing can be helped by adding straw or heat producing fresh horse manure inside the pot (but not directly on the crown).
Do not eat the rhubarb leaves as they contain high levels of oxalic acid which is toxic.
To promote more vigourous growth the next growing season do not harvest all the leaf stalks.
How to grow Rhubarb - Kitchen Notes
Used in combination with sugar - in crumbles, yoghurts, pies, trifles, fool or just with custard, Rhubarb is a very popular home grown vegetable.
Do not eat the rhubarb leaves or roots as they contain oxalic acid which is poisonous.
