Gardening Under Lights: Use HO T5 Lamps for Seedlings

June 17, 2020

Seedlings Need Bright Light

Once a seedling emerges from beneath the soil, both the amount of bright light and the duration of light are important. Seedlings need 14-16 hours of bright light to grow strong & study. If you notice your seedlings are elongating & stretching, they are not receiving enough light.

Look for HO T5 fluorescents when you’re shopping for growing lamps; skip the standard shop lights.
PC: Leslie F. Halleck

When I am growing seedlings, I use HO T5 fluorescent of LED fixtures that hold up to four lamps. These setups will provide the intense light that young seedlings need. The goal is to deliver even amounts of light to the entire seed tray - even the edges.

One of my grow shelves.
PC: Leslie F. Halleck

My Seedling Grow Light Set-up

I like to create grow shelves for my seedlings and cuttings with an adjustable shelving unit. I make shelves different heights for different sized plants, so I can move them around as they grow. I use large 4-foot fluorescent light fixtures (which can hold both HO T5 fluorescent and T5 LEDs) on these shelves in my garage, where there is no ambient light available.

If you have wire shelving in your garage, be sure to purchase plastic shelf covers so they will contain any water drainage.


Plant Parenting: Tomatoes can be Planted Deep

June 15, 2020

Some seedlings can be planted deeper in the soil than they were growing. Look below. Can you see the fuzzy part of the tomato stem that has a purple tint? You can bury that portion of tomato stem under the soil, as it will develop new adventitious bracing roots from that part of the stem.

So, if you accidentally waited too long to transplant, or your seedlings stretched due to lack of light, you can get your seedling back on track by planting a little deeper.

Tomato plug ready to be potted up.
PC: Leslie F. Halleck

Once I've checked the root system of my tomato plug & found it large enough for bumping up I filled a 4" pot with loose potting mix, then used a dibber to make a plug-sized hole for the tomato seedling. I dropped it into the hole & then gently pressed soil about the root ball & covered any exposed root area with some additional potting mix.

PC: Leslie F. Halleck

If you sniped this seedling off right at the soil line, you could also use it as a stem-tip cutting—the stem will grow new roots from the purple area.

Plant Parenting Book


Plant Parenting: Use Coir to Increase Humidity for Seeds

June 10, 2020

Maintaining proper moisture is key to successful germination and healthy seedlings. The growing media should always be damp to the touch, like a wrung-out sponge. Never let it dry out, but don't let it stay too soggy either.

A new seeding of peas topped with coir.
PC: Leslie F. Halleck

One trick to maintaining even moisture as seeds germinate and keep the surface of the soil from drying out is to sprinkle a thin layer of a material such as coir or vermiculite on top of the soil. I prefer to use coir. These materials will hold additional moisture, which can help prevent your seeds from drying out before they germinate.

Coir after it has been rehydrated.
PC: Leslie F. Halleck

Coir is a lightweight material made from the byproduct of coconut husks. It absorbs and holds water, while aerating the soil. Coir typically comes in a compressed block that you soak in water to rehydrate. After it soaks up water, coir becomes light and fluffy.


Plant Parenting: Thinning Out Seedlings

June 10, 2020

Once your seeds have germinated, it is time to thin their numbers. This part can be tough—no one wants to kill the seedlings they just grew.

When too many seeds germinate too closely together, the seedlings can struggle. It is tempting to let them all continue to grow, but your seedlings will be better off if you cull the weakest ones. More than one seedling per cell causes too much shading and resource competition, resulting in weaker seedlings overall.

If multiple seeds germinate in the same cell, keep the strongest and snip off the extras.
PC: Leslie F. Halleck

After your seeds have sprouted, choose the strongest, stockiest seedling in each cell and snip the remaining seedlings at the base. Throw the excess seedlings on your salad or feed them to any critters that would appreciate some greens.


Plant Parenting: Herb Stem-Tip Cuttings

June 8, 2020

When it comes to plant cloning, you'll probably take more stem cuttings than any other type. Herbs are a fantastic place to start multiplying your outdoor garden this spring as they are easy and quick to root by stem-tip cuttings.

Tip cuttings of oregano, watercress, lavender, thyme, rosemary, and a different variety of oregano.
PC: Leslie F. Halleck

Above, I used small short snips to remove a 2-inch section that contains two or three nodes along the stem. Each of these herbs will typically root directly in water, if I choose not to root them in a growing media. Make sure to remove any leaves that will be below the water or soil line.

I used a porcelain sprouting plate to keep cuttings from falling into water.
PC: Leslie F. Halleck

Don't overcrowd your cuttings. While you must maintain humidity around the cuttings during rooting, they also need good air circulation. Rooting media should be kept moist, but not soggy.

Herb stem-tip cuttings stuck in rockwool.
PC: Leslie F. Halleck

Herb tip cuttings can also be rooted in a lightweight growing media. Dip cutting in rooting hormone before sticking them. And be patient: while most herbs root relatively quickly, you will find that different plants will require more time than others.


Plant Parenting: How to Know When to Transplant

June 8, 2020

Two common mistakes that new plant propagators make include transplanting young seedlings or clones before they've developed a large enough root system -- or waiting too long to transplant. If you’re not sure how to gauge when a young plant is ready for transplanting to a larger container, the root system will tell you.

These tomato seedling shave started developing their first set of true leaves. Time to check their root growth!
PC: Leslie F. Halleck

After gently removing two plugs from the growing tray, I can see that the tomato seedling on the left has rooted completely to the bottom of the cell and is ready for transplanting. The plug on the right belongs to a slower-growing dwarf variety; its root system hasn’t quite filled the entire plug and some soil has fallen away when I removed it.

PC: Leslie F. Halleck

If you transplant too soon, you risk failure,since the root system isn't big enough to handle the disruption or a bigger pot with more soil.

Waiting too long may stunt the plant & they may not recover.


Plant Parenting: Crops Vary in Days-to-Harvest

June 3, 2020

Are you wondering when to start seeding your spring & summer vegetables? For all crops, you have to take the days-to-harvest into consideration.

Days-to-harvest varies, depending on whether you direct seed or transplant your edible crops.
PC: Leslie F. Halleck

The number of days-to-harvest can vary significantly, depending on whether you direct seed a crop into the garden or first grow a transplant. If you direct seed your crop into the garden or the container in which it will grow indoors, the days-to-harvest number on the seed packet is calculated from the date of germination.

For tomatoes, days-to-harvest start once they are planted into the garden.
PC: Leslie F. Halleck

Tropical crops, such as eggplant, peppers, and tomatoes, are typically started early indoors as transplants, allowing for bigger plants in the outdoor garden once temperatures are appropriate. For these crops, the days-to-harvest is counted from the date they are transplanted into their final container or outdoor garden location.

This is why you see southern gardeners starting their tomato seeds seeds indoors in January.


Texas: Lawn & Garden Tax Holiday!

May 1, 2020

Lawn & Garden Tax Holi​day ​Memorial Day Weekend 2020

Saturday, May 23 - Monday, May 25, 2020

The Lawn & Garden Tax Holiday was created in 2016 to encourage responsible water use in Texas. Over Memorial Day Weekend, retailers can sell select water saving products without charging sales tax (includes all plants & more). Below is a list of the items that qualify for the sales tax exemption:

Picture WaterSense Products During Memorial Day Weekend, retailers do not need to charge sales tax on any product tax free that displays a WaterSense label or logo. These items can be bought for either personal or business purposes.

Water-Conserving Products

Consumers can also purchase certain water-conserving products tax free. Unlike WaterSense-labeled items, these items are only exempt when purchased for use at a residential property.

Items are tax free during the holiday that are used or planted for:

  • conserving or retaining groundwater;
  • recharging water tables; or
  • decreasing ambient air temperature, and so limiting water evaporation

Examples of items that qualify for the exemption include:

  • a soaker or drip-irrigation hose
  • a moisture control for a sprinkler or irrigation system
  • mulch
  • a rain barrel or an alternative rain and moisture collection system
  • a permeable ground cover surface that allows water to reach underground basins, aquifers or water collection points
  • all plants, trees and grasses
  • water-saving surfactants
  • soil and compost

Examples of items that do not qualify for the exemption include:

  • construction/building materials
  • awnings and other items used to create shade
  • air conditioners
  • ceiling fans
  • sprinklers

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