Growing Dwarf Beans

Latest Update 27th August 2017.

Dwarf Beans
  • Dwarf beans like Italian Romano only grow to about 700mm and are useful ground cover and soil improvers when grown between my rows of climbing beans each summer.
  • Although not as productive as climbing beans, they don't shade them.
  • Their yield may be relatively low but they are just as nutritious and tasty as their taller cousins and well worth growing.
  • Legumes grow well in Ecobeds and are not usually affected by fungal diseases like powdery mildew because their foliage stays dry.
Details.
  • Binomial name:                                        Phaseolus vulgaris
  • Family group:                                           Fabaceae.
  • Variety:                                                    Italian Romano Bean.
  • Crop rotation group:                                  Legumes.
  • Garden bed type:                                      Garden Ecobed.
  • Recommended soil pH:                             6.0 - 7.5.
  • Minimum sun per day:                              8 hours.
  • Plant spacings (centres x rows):                150 x 150 mm.
  • Weeks to harvest:                                     9 - 11 weeks.
  • Good companion:                                     Beetroot. potato.
  • Climate:                                                   Warm temperate.
  • Geography:                                              Southern hemisphere. 
Nutrition.
  • This food is very low in saturated fat, cholesterol and sodium. 
  • It is a good source of protein, thiamin, magnesium, potassium and manganese, and a very good source of dietary fibre and folate.
  • More from nutrition data.self.com.
Growing Conditions: 
  • They grow best in warm sunny conditions and are frost tender.
  • They need well structured rich, moist organic soil.
Soil Preparation.
  • Clear a space for the beans in October and add a 60mm layer of home made compost.
  • Cover them with 50mm of fresh straw mulch.
  • Leave the bed for 4 weeks to build up worm and microbial activity.  
Growing Instructions. 
  • Clear space in the mulch in when ready to sow the beans.
  • Sow them in rows 150mm apart using a dibber (or your finger).
  • Make 30mm deep holes at 150mm intervals along each row and sow the beans.
  • Water them in well with dilute seaweed extract.
  • Return the mulch to cover the soil as soon as the beans are established. 
  • Apply a foliar spray of aerated compost tea every 4 weeks with all the other edible plants.
Harvesting and storage
  • Harvest the beans from March.
  • Pick them as soon as they fill their pods, as picking them early to encourage more flowers to grow.  
  • Use a pair of scissors to snip the pods off the bush to avoid damaging it. 
  • For best taste, cook the beans as soon as they are harvested.
  • They store well retaining their flavour and crisp texture if harvested young.  Just blanch them in boiling water for 2 minutes, dry them and put them in your freezer in zip bags. 
Organic Pest Control.
  • Slugs and snails.
    • Beans should be protected against slugs and snails using self adhesive copper tape bonded around the base of your Ecobeds.
    • If these molluscs get into your Ecobed as eggs laid in your compost, kill them with organically acceptable iron based snail pellets as soon as you discover them.  You should only need to use a small number of pellets.
  • Greenhouse whitefly.
    • Aerated compost tea strengthens the plants foliage against whitefly damage.  
    • Exclusion netting is effective against whitefly but they are very small and will occasionally breach your defences, so you will need to check your crop regularly. 
    • Control any infestations by spraying your crop thoroughly with organic horticultural oil (Eco-oil in Australia).
    • Spray again in a few days to ensure second generation whitefly do not survive.
  • Powdery mildew.  
    • Spray the bean's foliage with aerated compost tea every month to keep powdery mildew at bay.
    • A solution of 1 part cows milk to 9 parts water makes a reasonably effective organic pesticide against powdery mildew.  However, it needs to be applied early before the fungi gets well established, and regularly to keep the mildew in check.
    • As a last resort spray the plants foliage with organic fungicide (Eco-fungicide in Australia).
  • General:
    • Regular applications of aerated compost tea boost the natural defences of beans by colonising the leaf surfaces with beneficial microbes.  They defend the plant against airborne pests and diseases.
    • Similarly, proper soil preparation including regular applications of home made compost boosts the community of beneficial microbes which defend the plants roots against pathogens.
    • Exclusion netting can be used to stop birds digging up worms in your Ecobed while the plants are young, and takes the edge off hot sunshine with a 20% shade factor.  Remove the netting as soon as the beans begin to flower so pollinators can get good access to them.