Urban Harvest STL 5/26/20 Urban Harvest STL 5/26/20

Get Started: Why Fertilize?

All plants need light, water, and nutrients to thrive. Fertilizers can contribute nutrients to plant health, but a general rule of thumb is LESS is MORE. Heavy feeders like tomatoes often need additional nutrients that organic fertilizer can supplement; however, fertilizing is not the solution for most problems you encounter. Plants will only absorb the nutrients they require, and over-fertilizing can lead to wasted effort and a build-up of chemicals in your soil.

GARDEN AMENDMENTS

Soil amendments improve your soil’s nutrition and organic content, while fertilizers have specific nutrients to “feed” your plants. Most home vegetable gardens can avoid expensive fertilizers and focus on adding all-purpose organic material to soil to improve overall soil health and structure. Popular amendments include aged animal manures, worm castings, liquid fish emulsion, fall leaves, compost, perlite, straw, gypsum, and cover crops.

In general, you should add 2 inches of compost or aged manure on top of your garden beds and containers at the start of each year. Throughout the growing season, add a scoop of compost next to your seedlings and young plants periodically – a process known as side-dressing. You do not need to till or mix the compost into the soil; rain will saturate the top layer so that nutrients get absorbed.

WHEN TO USE FERTILIZER

Before you resort to fertilizer to help a struggling plant, review other factors: is the plant in a shady area and need more sun? Is the soil waterlogged or overly dry? Is your soil compacted or lacking adequate organic material? Are you dealing with pests or other pathogens? Is your soil’s pH out of balance?

If you are applying compost or amendments to your beds each year, you will need little to no fertilizer. In specific cases – such as when your plant is fruiting or if you are doing container gardening – some fertilizer may be helpful. Add a moderate amount of fertilizer when you transplant seedlings, early on in their growth. Organic fertilizers are slower-acting and gentler than chemical fertilizers and more appropriate to home vegetable gardening. Never add lawn fertilizer to your garden beds; the high nitrogen content will burn roots and cause imbalances in your soil.

FERTILIZER COMPOSITION

Commercial fertilizers are concentrated combinations of nutrients that are added to the soil to stimulate plant growth. Fertilizer labels include an N-P-K ratio that describes the percentage of (N) Nitrogen, (P) Phosphorus, and (K) Potassium (or Potash). For example, the label 5-3-2 indicates 5 parts nitrogen, 3 parts phosphorus, 2 parts potassium.

These are the 3 main elements that plants require to grow. Nitrogen is used in green plant growth, such as stems, roots, and leafy growth. Phosphorus is useful for strong roots and shoots, and potassium is essential for flowering and hardiness. Avoid high balanced ratios like 10-10-10 (often seen in lawn fertilizer), as this will do more damage than good. An ideal ratio for vegetables is 3-1-2.

Urban Harvest STL 4/10/20 Urban Harvest STL 4/10/20

Get Started: Worm Composting (Vermicompost 101)

WHAT IS WORM COMPOST?

Also known as vermicomposting, this technique uses an ecosystem of earthworms and microbes to break down organic material into a natural fertilizer called worm castings. Gardeners consider this to be “black gold” because castings have very high levels of microbial activity that enriches soil and promotes water retention. The most popular type of composting worms are called Red Wigglers. This is not the same species of earthworm that you find in your garden soil. They can tolerate a range of environments and are very efficient converters of organic material. At least 1 lb (approx 1000 worms) is recommended for starting a home system. A worm bin is one of the most efficient methods available for composting indoors!

How to build your urban worm bag.

OPTIONS FOR YOUR WORM BAG/BIN

DIY Plastic Tub: This requires a sturdy plastic (10 gallon) tub with holes drilled in the side and bottom for airflow. An option with this design is to “stack” one tub (with holes in the bottom for drainage) into another tub to catch excess moisture. To harvest finished compost, the worms must be separated from castings manually.
Stacking System: This is a popular alternative to the single bin because it avoids water-logged compost and the task of separating finished castings. These stacked bins are made of nesting trays that are placed on top of each other in a vertical tower. The trays have holes or mesh on the bottom, which allows worms to migrate upward when the food and bedding in the lower tray has been converted to castings.
Continuous Flow System: A single container that provides continuous finished castings without disturbing the worms. Food scraps and bedding are replenished on top of the system while the finished castings are removed from the bottom. Worms will naturally migrate to the upper 6 inches of the system where the food is plentiful, leaving their castings below for you to use. This is the design used by the Urban Worm Bag featured in our video tutorial.

Setting up the environment for your worm bed.

CREATING THE RIGHT ENVIRONMENT FOR YOUR BIN

Bedding materials: Popular options include coco coir, aged (not fresh!) horse manure, dry leaves, mature/finished compost, shredded paper and cardboard products including toilet paper rolls, paper egg cartons, and any newsprint that isn’t glossy or colored ink. Remember that the worms will also consume/convert their bedding so you do not want to add anything toxic or inorganic to the mix.
Microbes: A crucial part of the vermicomposting team! Microorganisms break down food scraps prior to worms consuming them. Add a scoop of compost when you start your bin to kickstart microbial activity. If you don’t have finished compost, a scoop of garden topsoil is an excellent alternative.
Moisture: Ideal moisture content is about 60%. The simplest way to determine if your bin is in this range is to squeeze a handful of your compost. You should get 1 drop of water. If the castings are crumbly, the bin is too dry, and you can add more food or water (use mist or spray bottle only). If you get more than 1 drop of water or it’s “muddy,” it is too wet. Add bedding and stop feeding for a period of time.
Temperature: Unlike an outdoor compost bin, the microbes in your worm bin do not need hot temperatures. In fact, the right temperature range in your bin is 40-85° Fahrenheit, but does best at 60-75 ℉. Overfeeding leads to overheating!
pH: This should be neutral to slightly acidic. You can maintain this balance by adding fresh bedding with food scraps. Only add moderate amounts of acidic foods like berries or citrus. Occasionally adding ground egg shells will also help counteract the acidity of food scraps (and the grit is good for worm digestion!)

FEEDING YOUR WORMS

Adding your worms

Feeding your worms

Suitable worm food: Worms can eat most fruit and vegetable scraps, grains such as plain rice and oatmeal, coffee grounds, crushed egg shells, pulp from a juicer, small amounts of bread, and used tea bags. Worms will process shredded or cut up food more quickly and love food that microbes have already started to consume. You can leave food scraps in a container for a few days before adding to the bin. Do you have some veggies in your fridge that are slightly mushy, or brown bananas? This is perfect worm food!
Unsuitable foods: Do not feed your worms butter, meat, dairy, bones, oils, salty foods, grass clippings, citrus, onions, hot pepper, spicy food, pickles or vinegar, pasta, wood ash, and pet feces. Worms do not process these foods well, so they may be left to rot and create odor or breed undesirable bacteria in the bin.
Frequency: Add 25-33% of the weight of your worms every 3 days and observe if the worms finish processing that food before adding fresh scraps. If you see rotting food on top of the bin, they are not consuming it quickly enough and you should add less food.
- Rough guideline for volume conversion of food waste: 1 lb ≅ 4 cups or 1 qt.
Overfeeding: This is the most common error that beginners make. Is your bin too wet or too hot? Does it have an unpleasant odor? You are overfeeding! Add dry bedding and stop feeding until conditions stabilize.

FINISHED WORM CASTINGS

Most vermicompost systems will produce usable worm castings in 8-12 weeks, which is quicker than traditional composting. Finished vermicompost is dark, earthy smelling and moist but not soaking.
Castings can be added directly into a potting mix or used to “side dress” your plants and seedlings!